start of rom_only PC

Cargo.lock

@@ -366,6 +366,7 @@ checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
 name = "macroquad"
 version = "0.1.0"
 dependencies = [
+ "core",
  "macroquad 0.4.14",
 ]
 

beneater/src/bin/beneater.rs

@@ -1,9 +1,9 @@
 // This is the GUI for the BenEater PC
+use beneater::parts::backplane::Backplane;
+use beneater::parts::ben_eater_pc::BenEaterPC;
 use beneater::parts::cpu_display::CpuDisplay;
 use macroquad::prelude::*;
 use macroquad::telemetry::frame;
-use beneater::parts::ben_eater_pc::BenEaterPC;
-use beneater::parts::backplane::Backplane;
 #[macroquad::main("Ben Eaters PC")]
 async fn main() {
     println!("Taxation is Theft");
@@ -21,7 +21,7 @@ async fn main() {
 
         draw_text("Ben Eater", 20.0, 20.0, 30.0, BLACK);
         dm.render(20.0, 40.0);
-      //  CpuDisplay::render(&computer.cpu, 20.0, 120.0);
+        //  CpuDisplay::render(&computer.cpu, 20.0, 120.0);
 
         frame_number += 1;
 

beneater/src/bin/make_rom.rs

@@ -1,5 +1,5 @@
-use std::fs;
 use core::constants::constants_system::SIZE_32KB;
+use std::fs;
 
 fn main() {
     // make the rom data in memory.

beneater/src/bin/urn.rs

@@ -1,20 +1,24 @@
+use beneater::parts::backplane::Backplane;
+use core::constants::constants_isa_op::*;
+use core::constants::constants_system::*;
 use std::fs;
 use std::ops::Index;
-use beneater::parts::backplane::Backplane;
-use core::constants::constants_system::*;
-use core::constants::constants_isa_op::*;
 fn main() {
     println!("Taxation is Theft");
 
     let mut backplane = Backplane::new();
 
+    backplane.load_rom();
     println!("Backplane is live.");
 
     let mut new_program = [0x00u8; SIZE_32KB];
     new_program[(OFFSET_RESET_VECTOR - SIZE_32KB as u16) as usize] = 0x00;
     new_program[(OFFSET_RESET_VECTOR + 1 - SIZE_32KB as u16) as usize] = 0x60;
     println!("Set offset in rom...");
-    println!("VALUE AT OFFSET_RESET_VECTOR = 0x{:02x} ", new_program[(OFFSET_RESET_VECTOR - SIZE_32KB as u16) as usize]);
+    println!(
+        "VALUE AT OFFSET_RESET_VECTOR = 0x{:02x} ",
+        new_program[(OFFSET_RESET_VECTOR - SIZE_32KB as u16) as usize]
+    );
     // println!("{:?}", new_program);
 
     backplane.rom.program(&new_program);
@@ -22,5 +26,4 @@ fn main() {
     backplane.memory[0x6000] = ISA_OP_LDA_I;
     backplane.memory[0x6001] = 0xab;
     backplane.tick();
-
 }

beneater/src/lib.rs

@@ -1 +1,3 @@
 pub mod parts;
+pub mod backplane;
+mod backplane;

beneater/src/parts/address_bus.rs

@@ -1,9 +1,9 @@
 pub struct AddressBus {
-    pub address: u16
+    pub address: u16,
 }
 
 impl AddressBus {
     pub fn new() -> Self {
         AddressBus { address: 0x0000 }
     }
-}
+}

beneater/src/parts/backplane.rs

@@ -1,15 +1,27 @@
-use core::mos6502cpu::Mos6502Cpu;
 use crate::parts::mos6522_peripheral::Mos6522Peripheral;
 use crate::parts::via6522::VIA6522;
 use core::constants::constants_system::*;
+use core::mos6502cpu::Mos6502Cpu;
 use core::periph::at28c256::At28C256;
 use core::periph::rom_chip::RomChip;
+
+/// Backplane
+///
+/// A Backplane hold and coordinates the cpu with the
+/// rest of the peripherals.
+///
+/// This system has
+/// -> VIA6522 for peripherals
+/// -> 322KB RAM
+/// -> 32KB ROM
 pub struct Backplane {
     // pub for dev
     pub cpu: Mos6502Cpu,
     pub via: VIA6522,
-    pub memory: Box<[u8; SIZE_64KB]>,
-    pub rom: At28C256
+    pub memory: Box<[u8; SIZE_32KB]>,
+    pub rom: At28C256,
+    data_bus: u8,
+    address_bus: u16
 }
 
 impl Backplane {
@@ -17,8 +29,10 @@ impl Backplane {
         Backplane {
             cpu: Mos6502Cpu::default(),
             via: VIA6522::default(),
-            memory: Box::new([0x00; SIZE_64KB]),
-            rom: At28C256::default()
+            memory: Box::new([0x00; SIZE_32KB]),
+            rom: At28C256::default(),
+            data_bus: 0x00,
+            address_bus: 0x0000
         }
     }
 
@@ -28,46 +42,85 @@ impl Backplane {
 
     pub fn tick(&mut self) {
         // is the CPU in read or write state
-        let address = self.cpu.address_bus();
-        let data = self.cpu.data_bus();
+        self.address_bus = self.cpu.address_bus();
+        self.data_bus = self.cpu.data_bus();
         let rw = self.cpu.read_signal;
         println!("- TICK START:");
-        println!("| CPU: Address: 0b{address:016b} Data: 0b{data:08b} CPU RW: {rw}");
+        println!("| CPU: Address: 0b{:016b} Data: 0b{:08b} CPU RW: {rw}", self.address_bus, self.data_bus);
         // via state
-        println!("| VIA 0b{:08b}/0b{:08b}/0b{:08b}/0b{:08b}/",
+        println!(
+            "| VIA 0b{:08b}/0b{:08b}/0b{:08b}/0b{:08b}/",
             self.via.read(VIA6522_ORA),
             self.via.read(VIA6522_ORA),
             self.via.read(VIA6522_DDRB),
             self.via.read(VIA6522_DDRA),
         );
         println!("| LCD");
-        match address {
-            /// VIA
-            0x6000..0x6010 => {
-                if self.cpu.read_signal {
-                    self.cpu.set_data_bus(self.via.read((address - 0x6000) as u8));
-                } else {
-                    self.via.write((address - 0x6000) as u8, self.cpu.data_bus());
+
+
+        // if we are reading
+        if rw {
+            println!("CPU HAS SET READ FLAG FOR ADDRESS {address:04x} with data 0x{data:02x}");
+            match self.address_bus {
+                0x0000..=0x3fff => {
+                    // read from ram
+
+                },
+                0x4000..=0x7fff => {
+                    // read from ROM
+
                 }
-                self.via.tick();
-            }
-            /// RAM
-            0x0000..=0x3fff => {
-                if self.cpu.read_signal {
-                    self.cpu.set_data_bus(self.memory[address as usize]);
-                } else {
-                    self.memory[address as usize] = data;
+                _ => {
+                    println!("READ OUTSIDE DATA RANGE");
                 }
             }
-            /// ROM
-            0x4000..=0x7fff => {
-                self.rom.read(&(address - 0x4000));
-            }
-            /// The ether.  Scarrrrrrrryyyy......
-            _ => {
-                println!("Lost READ:?{} to {:04x}", self.cpu.read_signal, address);
+        } else {
+            println!("CPU HAS SET WRITE FLAG FOR ADDRESS 0x{address:04x} with data 0x{data:02x}");
+            match self.address_bus {
+                0x6000..=0x600f => {
+                    self.via.write((self.address_bus - 0x6000) as u8, self.data_bus);
+                },
+                0x0000..=0x3fff => {
+                    self.memory[self.address_bus] = self.data_bus;
+                }
+                _ => {
+                    println!("ATTEMPT TO WRITE OUTSIDE OF MEMORY");
+                }
             }
         }
+
+        //
+        //
+        // match address {
+        //     /// VIA
+        //     0x6000..=0x600f => {
+        //         if self.cpu.read_signal {
+        //             self.cpu
+        //                 .set_data_bus(self.via.read((address - 0x6000) as u8));
+        //         } else {
+        //             self.via
+        //                 .write((address - 0x6000) as u8, self.cpu.data_bus());
+        //         }
+        //         self.via.tick();
+        //     }
+        //     /// RAM
+        //     0x0000..=0x3fff => {
+        //         if self.cpu.read_signal {
+        //             self.cpu.set_data_bus(self.memory[address as usize]);
+        //         } else {
+        //             self.memory[address as usize] = data;
+        //         }
+        //     }
+        //     /// ROM
+        //     0x4000..=0x7fff => {
+        //         println!("ROM READ AT {address:04x} / ROM OFFSET {:04x}", address - 0x4000);
+        //         self.rom.read(&(address - 0x4000));
+        //     }
+        //     /// The ether.  Scarrrrrrrryyyy......
+        //     _ => {
+        //         println!("XXXXLost READ:?{} to {:04x}", self.cpu.read_signal, address);
+        //     }
+        // }
         println!("- TICK DONE");
     }
-}
+}

beneater/src/parts/ben_eater_pc.rs

@@ -1,10 +1,10 @@
+use crate::parts::clock::Clock;
+use core::constants::constants_system::*;
+use core::mos6502cpu::Mos6502Cpu;
 use std::fs;
 use std::fs::File;
 use std::io::{BufReader, Read};
 use std::path::Path;
-use crate::parts::clock::Clock;
-use core::mos6502cpu::Mos6502Cpu;
-use core::constants::constants_system::*;
 
 pub struct BenEaterPC {
     clock: Clock,
@@ -19,11 +19,11 @@ impl BenEaterPC {
         println!("New BENEATERPC");
         BenEaterPC {
             clock: Clock::new(),
-            cpu: Mos6502Cpu::default()
+            cpu: Mos6502Cpu::default(),
         }
     }
 
-    pub fn tick_system(&mut self)  {
+    pub fn tick_system(&mut self) {
         self.cpu.tick();
         if self.cpu.microcode_step == 0 {
             // tick the clock.

beneater/src/parts/clock.rs

@@ -1,13 +1,10 @@
 pub struct Clock {
-    ticks: u32
+    ticks: u32,
 }
 
 impl Clock {
     pub fn new() -> Self {
-
-        Clock {
-            ticks: 0
-        }
+        Clock { ticks: 0 }
     }
 
     pub fn tick(&mut self) {

beneater/src/parts/cpu_display.rs

@@ -1,7 +1,7 @@
+use core::mos6502cpu::Mos6502Cpu;
 use macroquad::color::{BLACK, Color};
 use macroquad::prelude::*;
 use macroquad::text::draw_text;
-use core::mos6502cpu::Mos6502Cpu;
 
 pub struct CpuDisplay {}
 impl CpuDisplay {
@@ -12,11 +12,41 @@ impl CpuDisplay {
         // ...build the interface
         Self::draw_square(x_offset, y_offset, x_offset + 300.0, y_offset + 85.0, BLACK);
 
-        draw_text(format!("PC: 0x{:04x} / {}", pc, pc).as_str(), x_offset + 5.0, y_offset + 18.0, 15.0, BLACK);
-        draw_text(format!("A: 0x{:02x} X: 0x{:02x} Y: 0x{:02x}", a, x, y).as_str(), x_offset + 5.0, y_offset + 35.0, 15.0, BLACK);
-        draw_text(format!("Address: {:016b} | {:04x}", address_bus, address_bus).as_str(), x_offset + 5.0, y_offset + 55.0, 15.0, BLACK);
-        draw_text(format!("Data: {:08b} | {:02x}", data_bus, data_bus).as_str(), x_offset + 5.0, y_offset + 75.0, 15.0, BLACK);
-        draw_text(format!("MS: {:02x}", microsteps_remaining).as_str(), x_offset + 5.0, y_offset + 95.0, 15.0, BLACK);
+        draw_text(
+            format!("PC: 0x{:04x} / {}", pc, pc).as_str(),
+            x_offset + 5.0,
+            y_offset + 18.0,
+            15.0,
+            BLACK,
+        );
+        draw_text(
+            format!("A: 0x{:02x} X: 0x{:02x} Y: 0x{:02x}", a, x, y).as_str(),
+            x_offset + 5.0,
+            y_offset + 35.0,
+            15.0,
+            BLACK,
+        );
+        draw_text(
+            format!("Address: {:016b} | {:04x}", address_bus, address_bus).as_str(),
+            x_offset + 5.0,
+            y_offset + 55.0,
+            15.0,
+            BLACK,
+        );
+        draw_text(
+            format!("Data: {:08b} | {:02x}", data_bus, data_bus).as_str(),
+            x_offset + 5.0,
+            y_offset + 75.0,
+            15.0,
+            BLACK,
+        );
+        draw_text(
+            format!("MS: {:02x}", microsteps_remaining).as_str(),
+            x_offset + 5.0,
+            y_offset + 95.0,
+            15.0,
+            BLACK,
+        );
     }
 
     fn draw_square(x1: f32, y1: f32, x2: f32, y2: f32, color: Color) {
@@ -26,4 +56,4 @@ impl CpuDisplay {
         draw_line(x1, y2, x2, y2, 1.0, color);
         draw_line(x2, y1, x2, y2, 1.0, color);
     }
-}
+}

beneater/src/parts/data_bus.rs

@@ -1,9 +1,9 @@
 pub struct DataBus {
-    pub data: u8
+    pub data: u8,
 }
 
 impl DataBus {
     pub fn new() -> Self {
         DataBus { data: 0x00 }
     }
-}
+}

beneater/src/parts/display_matrix.rs

@@ -1,5 +1,5 @@
-use std::time::{Duration, Instant};
 use crate::parts::mos6522_peripheral::Mos6522Peripheral;
+use std::time::{Duration, Instant};
 
 #[derive(Debug)]
 pub struct HD44780 {
@@ -46,7 +46,7 @@ impl Mos6522Peripheral for HD44780 {
         self.write_control_lines(
             control & 1 << 2 == 0,
             control & 1 << 1 == 0,
-            control & 1 == 0
+            control & 1 == 0,
         );
     }
 

beneater/src/parts/mod.rs

@@ -1,10 +1,10 @@
-pub mod clock;
-pub mod ben_eater_pc;
-pub mod via6522;
-pub mod display_matrix;
 pub mod address_bus;
-pub mod data_bus;
-pub mod cpu_display;
-pub mod ram_display;
-pub mod mos6522_peripheral;
 pub mod backplane;
+pub mod ben_eater_pc;
+pub mod clock;
+pub mod cpu_display;
+pub mod data_bus;
+pub mod display_matrix;
+pub mod mos6522_peripheral;
+pub mod ram_display;
+pub mod via6522;

beneater/src/parts/ram_display.rs

@@ -4,10 +4,15 @@ pub struct RamDisplay {}
 
 impl RamDisplay {
     pub fn render(ram: &Box<[u8]>, x_offset: f32, y_offset: f32) {
-        Self::draw_square(x_offset, y_offset, x_offset + 200.0, y_offset + 300.0, BLACK);
+        Self::draw_square(
+            x_offset,
+            y_offset,
+            x_offset + 200.0,
+            y_offset + 300.0,
+            BLACK,
+        );
 
         draw_text("RAM", x_offset + 5.0, y_offset + 5.0, 15.0, BLACK);
-
     }
 
     fn draw_square(x1: f32, y1: f32, x2: f32, y2: f32, color: Color) {
@@ -17,4 +22,4 @@ impl RamDisplay {
         draw_line(x1, y2, x2, y2, 1.0, color);
         draw_line(x2, y1, x2, y2, 1.0, color);
     }
-}
+}

beneater/src/parts/via6522.rs

@@ -57,7 +57,6 @@ impl VIA6522 {
         }
     }
 
-
     pub fn read(&self, addr: u8) -> u8 {
         match (addr & 0x0F) {
             VIA6522_ORB => self.orb,

cli/src/bin/decode.rs

@@ -1,5 +1,5 @@
-use core::instruction::Instruction;
 use core::address_mode::AddressMode;
+use core::instruction::Instruction;
 use core::operand::Operand;
 use core::operation::Operation;
 
@@ -11,12 +11,13 @@ fn main() {
             op: Operation::NOP,
             mode: AddressMode::Implied,
             operand: Operand::None,
-        }, &[0xea]
-        )];
+        },
+        &[0xea],
+    )];
 
     for (op, bytes) in instructions {
         assert_eq!(Instruction::decode(bytes), Some(op));
     }
-  //  let instruction = Instruction::decode(&[0xea]);
-  //  println!("NOP Decoded -> {:?}", instruction);
+    //  let instruction = Instruction::decode(&[0xea]);
+    //  println!("NOP Decoded -> {:?}", instruction);
 }

cli/src/bin/ticker.rs

@@ -1,7 +1,5 @@
 use core::mos6502cpu::Mos6502Cpu;
 
 fn main() {
-
     let x = Mos6502Cpu::default();
-
-}
+}

core/Cargo.toml

@@ -4,4 +4,4 @@ version = "0.1.0"
 edition = "2024"
 [dependencies]
 log = "0.4"
-rand = "0.9.0"
+rand = "0.9.0"

core/src/address_mode.rs

@@ -1,4 +1,3 @@
-
 /// Represents the various addressing modes of the 6502 CPU.
 #[derive(PartialEq, Debug, Copy, Clone)]
 pub enum AddressMode {

core/src/computers/beneater/beneater.rs

@@ -1,9 +1,5 @@
-
 /// BenEater computer represents the 'Ben Eater' 6502 breadboard computer.
 /// This was built along watching the video series where Ben builds a
 /// 6502 on a breadboard and explains each step.
 ///
-pub struct BenEater {
-
-}
-
+pub struct BenEater {}

core/src/computers/mod.rs

@@ -1,2 +1,2 @@
 pub mod beneater;
-
+pub mod rom_only;

core/src/computers/rom_only/backplane.rs

@@ -0,0 +1,25 @@
+use crate::constants::constants_system::{SIZE_32KB, SIZE_64KB};
+use crate::periph::hm62256::Hm62256;
+use crate::periph::rom_chip::RomChip;
+
+pub struct Backplane {
+    rom: Hm62256
+}
+
+impl Backplane {
+    pub fn new() -> Backplane {
+        Backplane::program(&[0x00; SIZE_32KB])
+    }
+    
+    pub fn program(rom: &[u8; SIZE_32KB]) -> Backplane {
+        Backplane {
+            rom: *Hm62256::program(rom)
+        }
+    }
+    
+    pub fn tick(&mut self) {
+        println!("Preparing to tick.");
+        
+        println!("Done ticking.");
+    }
+}

core/src/computers/rom_only/mod.rs

@@ -0,0 +1 @@
+pub mod backplane;

core/src/constants/constants_isa_op.rs

@@ -107,7 +107,6 @@ pub const ISA_OP_LDY_ZP: u8 = 0xa4;
 pub const ISA_OP_LDY_ZPX: u8 = 0xb4;
 pub const ISA_OP_LDY_ABS: u8 = 0xac;
 pub const ISA_OP_LDY_ABSX: u8 = 0xbc;
-
 pub const ISA_OP_LSR_A: u8 = 0x4a;
 pub const ISA_OP_LSR_ZP: u8 = 0x46;
 pub const ISA_OP_LSR_ZPX: u8 = 0x56;
@@ -167,4 +166,4 @@ pub const ISA_OP_TAY: u8 = 0xa8;
 pub const ISA_OP_TSX: u8 = 0xba;
 pub const ISA_OP_TXA: u8 = 0x8a;
 pub const ISA_OP_TXS: u8 = 0x9a;
-pub const ISA_OP_TYA: u8 = 0x98;
+pub const ISA_OP_TYA: u8 = 0x98;

core/src/constants/constants_isa_stub.rs

@@ -54,4 +54,4 @@ pub const ISA_STUB_TAY: &str = "TAY";
 pub const ISA_STUB_TSX: &str = "TSX";
 pub const ISA_STUB_TXA: &str = "TXA";
 pub const ISA_STUB_TXS: &str = "TXS";
-pub const ISA_STUB_TYA: &str = "TYA";
+pub const ISA_STUB_TYA: &str = "TYA";

core/src/constants/constants_system.rs

@@ -5,7 +5,6 @@ pub const SIZE_64KB: usize = SIZE_1KB * 64;
 pub const OFFSET_RESET_VECTOR: u16 = 0xfffc;
 pub const OFFSET_INT_VECTOR: u16 = 0xfffe;
 
-
 pub const VIA6522_ORB: u8 = 0;
 pub const VIA6522_ORA: u8 = 1;
 pub const VIA6522_DDRB: u8 = 2;

core/src/constants/mod.rs

@@ -1,3 +1,3 @@
-pub mod constants_isa_stub;
 pub mod constants_isa_op;
+pub mod constants_isa_stub;
 pub mod constants_system;

core/src/instruction2/from_bytes.rs

@@ -1,23 +0,0 @@
-use log::debug;
-use crate::address_mode::AddressMode::*;
-use crate::constants::constants_isa_op::*;
-
-fn join_word(low: u8, high: u8) -> u16 {
-    ((high as u16) << 8) | low as u16
-}
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    #[test]
-    fn test_join_word() {
-        let low: u8 = 0xcd;
-        let high: u8 = 0xab;
-
-        assert_eq!(
-            join_word(low, high),
-            0xabcd
-        );
-    }
-}

core/src/instruction2/mod.rs

@@ -1,7 +0,0 @@
-use crate::address_mode::AddressMode;
-use crate::address_mode::AddressMode::*;
-use crate::mos6502flags::Mos6502Flag::*;
-
-mod from_bytes;
-mod to_bytes;
-mod to_string;

core/src/instruction2/to_bytes.rs

@@ -1,38 +0,0 @@
-use crate::address_mode::AddressMode;
-use crate::address_mode::AddressMode::{Absolute, AbsoluteX, AbsoluteY, Immediate, IndirectX, IndirectY, ZeroPage, ZeroPageX, ZeroPageY};
-use crate::constants::constants_isa_op::*;
-
-fn split_word_hl(to_split: u16) -> (u8, u8) {
-    let low = (to_split & 0xff) as u8;
-    let high = ((to_split & 0xff00) >> 8) as u8;
-    (high, low)
-}
-
-fn split_word_lh(to_split: u16) -> (u8, u8) {
-    let low = (to_split & 0xff) as u8;
-    let high = ((to_split & 0xff00) >> 8) as u8;
-    (low, high)
-}
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    #[test]
-    fn split_le() {
-        let value = 0xabcd;
-        let (high, low) = split_word_hl(value);
-
-        assert_eq!(low, 0xcd);
-        assert_eq!(high, 0xab);
-    }
-
-    #[test]
-    fn split_be() {
-        let value = 0xabcd;
-        let (low, high) = split_word_lh(value);
-
-        assert_eq!(low, 0xcd);
-        assert_eq!(high, 0xab);
-    }
-}

core/src/instruction2/to_string.rs

@@ -1,18 +0,0 @@
-
-fn format(mode: &AddressMode, prefix: &str) -> String {
-    // let suffix = match mode {
-    //     AddressMode::Implied => "",
-    //     AddressMode::Accumulator => " A",
-    //     AddressMode::Immediate(value) => &*format!(" #${value:02x}"),
-    //     AddressMode::ZeroPage(value) => &*format!(" ${value:02x}"),
-    //     AddressMode::ZeroPageX(value) => &*format!(" ${value:02x},X"),
-    //     AddressMode::Absolute(offset) => &*format!(" ${offset:04x}"),
-    //     AddressMode::AbsoluteX(offset) => &*format!(" ${offset:04x},X"),
-    //     AddressMode::AbsoluteY(offset) => &*format!(" ${offset:04x},Y"),
-    //     AddressMode::IndirectX(value) => &*format!(" (${value:02x},X)"),
-    //     AddressMode::IndirectY(value) => &*format!(" (${value:02x}),Y"),
-    //     AddressMode::ZeroPageY(value) => &*format!(" ${value:02x},Y")
-    // };
-    // format!("{}{}", prefix, suffix)
-    prefix.to_string()
-}

core/src/instruction_table.rs

@@ -1,10 +1,36 @@
 use crate::address_mode::AddressMode;
-use crate::constants::constants_isa_op::{ISA_OP_ADC_ABS, ISA_OP_ADC_ABSX, ISA_OP_ADC_ABSY, ISA_OP_ADC_I, ISA_OP_ADC_INDX, ISA_OP_ADC_INDY, ISA_OP_ADC_Z, ISA_OP_ADC_ZX, ISA_OP_AND_ABS, ISA_OP_AND_ABSX, ISA_OP_AND_ABSY, ISA_OP_AND_I, ISA_OP_AND_INDX, ISA_OP_AND_INDY, ISA_OP_AND_Z, ISA_OP_AND_ZX, ISA_OP_ASL_A, ISA_OP_ASL_ABS, ISA_OP_ASL_ABSX, ISA_OP_ASL_Z, ISA_OP_ASL_ZX, ISA_OP_BCC, ISA_OP_BCS, ISA_OP_BEQ, ISA_OP_BIT_ABS, ISA_OP_BIT_ZP, ISA_OP_BMI, ISA_OP_BNE, ISA_OP_BPL, ISA_OP_BRK, ISA_OP_BVC, ISA_OP_BVS, ISA_OP_CLC, ISA_OP_CLD, ISA_OP_CLI, ISA_OP_CLV, ISA_OP_CMP_ABS, ISA_OP_CMP_ABSX, ISA_OP_CMP_ABSY, ISA_OP_CMP_I, ISA_OP_CMP_INDX, ISA_OP_CMP_INDY, ISA_OP_CMP_ZP, ISA_OP_CMP_ZPX, ISA_OP_CPX_ABS, ISA_OP_CPX_I, ISA_OP_CPX_ZP, ISA_OP_CPY_ABS, ISA_OP_CPY_I, ISA_OP_CPY_ZP, ISA_OP_DEC_ABS, ISA_OP_DEC_ABSX, ISA_OP_DEC_ZP, ISA_OP_DEC_ZPX, ISA_OP_DEX, ISA_OP_DEY, ISA_OP_EOR_ABS, ISA_OP_EOR_ABSX, ISA_OP_EOR_ABSY, ISA_OP_EOR_I, ISA_OP_EOR_INDX, ISA_OP_EOR_INDY, ISA_OP_EOR_ZP, ISA_OP_EOR_ZPX, ISA_OP_INC_ABS, ISA_OP_INC_ABSX, ISA_OP_INC_ZP, ISA_OP_INC_ZPX, ISA_OP_INX, ISA_OP_INY, ISA_OP_JMP_ABS, ISA_OP_JMP_IND, ISA_OP_JSR, ISA_OP_LDA_ABS, ISA_OP_LDA_ABSX, ISA_OP_LDA_ABSY, ISA_OP_LDA_I, ISA_OP_LDA_INDX, ISA_OP_LDA_INDY, ISA_OP_LDA_Z, ISA_OP_LDA_ZX, ISA_OP_LDX_ABS, ISA_OP_LDX_ABSY, ISA_OP_LDX_I, ISA_OP_LDX_ZP, ISA_OP_LDX_ZPY, ISA_OP_LDY_ABS, ISA_OP_LDY_ABSX, ISA_OP_LDY_I, ISA_OP_LDY_ZP, ISA_OP_LDY_ZPX, ISA_OP_LSR_A, ISA_OP_LSR_ABS, ISA_OP_LSR_ABSX, ISA_OP_LSR_ZP, ISA_OP_LSR_ZPX, ISA_OP_NOP, ISA_OP_ORA_ABS, ISA_OP_ORA_ABSX, ISA_OP_ORA_ABSY, ISA_OP_ORA_I, ISA_OP_ORA_INDX, ISA_OP_ORA_INDY, ISA_OP_ORA_ZP, ISA_OP_ORA_ZPX, ISA_OP_PHA, ISA_OP_PHP, ISA_OP_PLA, ISA_OP_PLP, ISA_OP_ROL_A, ISA_OP_ROL_ABS, ISA_OP_ROL_ABSX, ISA_OP_ROL_ZP, ISA_OP_ROL_ZPX, ISA_OP_ROR_A, ISA_OP_ROR_ABS, ISA_OP_ROR_ABSX, ISA_OP_ROR_ZP, ISA_OP_ROR_ZPX, ISA_OP_RTI, ISA_OP_RTS, ISA_OP_SBC_ABS, ISA_OP_SBC_ABSX, ISA_OP_SBC_ABSY, ISA_OP_SBC_I, ISA_OP_SBC_INDX, ISA_OP_SBC_INDY, ISA_OP_SBC_ZP, ISA_OP_SBC_ZPX, ISA_OP_SEC, ISA_OP_SED, ISA_OP_SEI, ISA_OP_STA_ABS, ISA_OP_STA_ABSX, ISA_OP_STA_ABSY, ISA_OP_STA_INDX, ISA_OP_STA_INDY, ISA_OP_STA_ZP, ISA_OP_STA_ZPX, ISA_OP_STX_ABS, ISA_OP_STX_ZP, ISA_OP_STX_ZPY, ISA_OP_STY_ABS, ISA_OP_STY_ZP, ISA_OP_STY_ZPX, ISA_OP_TAX, ISA_OP_TAY, ISA_OP_TSX, ISA_OP_TXA, ISA_OP_TXS, ISA_OP_TYA};
+use crate::constants::constants_isa_op::{
+    ISA_OP_ADC_ABS, ISA_OP_ADC_ABSX, ISA_OP_ADC_ABSY, ISA_OP_ADC_I, ISA_OP_ADC_INDX,
+    ISA_OP_ADC_INDY, ISA_OP_ADC_Z, ISA_OP_ADC_ZX, ISA_OP_AND_ABS, ISA_OP_AND_ABSX, ISA_OP_AND_ABSY,
+    ISA_OP_AND_I, ISA_OP_AND_INDX, ISA_OP_AND_INDY, ISA_OP_AND_Z, ISA_OP_AND_ZX, ISA_OP_ASL_A,
+    ISA_OP_ASL_ABS, ISA_OP_ASL_ABSX, ISA_OP_ASL_Z, ISA_OP_ASL_ZX, ISA_OP_BCC, ISA_OP_BCS,
+    ISA_OP_BEQ, ISA_OP_BIT_ABS, ISA_OP_BIT_ZP, ISA_OP_BMI, ISA_OP_BNE, ISA_OP_BPL, ISA_OP_BRK,
+    ISA_OP_BVC, ISA_OP_BVS, ISA_OP_CLC, ISA_OP_CLD, ISA_OP_CLI, ISA_OP_CLV, ISA_OP_CMP_ABS,
+    ISA_OP_CMP_ABSX, ISA_OP_CMP_ABSY, ISA_OP_CMP_I, ISA_OP_CMP_INDX, ISA_OP_CMP_INDY,
+    ISA_OP_CMP_ZP, ISA_OP_CMP_ZPX, ISA_OP_CPX_ABS, ISA_OP_CPX_I, ISA_OP_CPX_ZP, ISA_OP_CPY_ABS,
+    ISA_OP_CPY_I, ISA_OP_CPY_ZP, ISA_OP_DEC_ABS, ISA_OP_DEC_ABSX, ISA_OP_DEC_ZP, ISA_OP_DEC_ZPX,
+    ISA_OP_DEX, ISA_OP_DEY, ISA_OP_EOR_ABS, ISA_OP_EOR_ABSX, ISA_OP_EOR_ABSY, ISA_OP_EOR_I,
+    ISA_OP_EOR_INDX, ISA_OP_EOR_INDY, ISA_OP_EOR_ZP, ISA_OP_EOR_ZPX, ISA_OP_INC_ABS,
+    ISA_OP_INC_ABSX, ISA_OP_INC_ZP, ISA_OP_INC_ZPX, ISA_OP_INX, ISA_OP_INY, ISA_OP_JMP_ABS,
+    ISA_OP_JMP_IND, ISA_OP_JSR, ISA_OP_LDA_ABS, ISA_OP_LDA_ABSX, ISA_OP_LDA_ABSY, ISA_OP_LDA_I,
+    ISA_OP_LDA_INDX, ISA_OP_LDA_INDY, ISA_OP_LDA_Z, ISA_OP_LDA_ZX, ISA_OP_LDX_ABS, ISA_OP_LDX_ABSY,
+    ISA_OP_LDX_I, ISA_OP_LDX_ZP, ISA_OP_LDX_ZPY, ISA_OP_LDY_ABS, ISA_OP_LDY_ABSX, ISA_OP_LDY_I,
+    ISA_OP_LDY_ZP, ISA_OP_LDY_ZPX, ISA_OP_LSR_A, ISA_OP_LSR_ABS, ISA_OP_LSR_ABSX, ISA_OP_LSR_ZP,
+    ISA_OP_LSR_ZPX, ISA_OP_NOP, ISA_OP_ORA_ABS, ISA_OP_ORA_ABSX, ISA_OP_ORA_ABSY, ISA_OP_ORA_I,
+    ISA_OP_ORA_INDX, ISA_OP_ORA_INDY, ISA_OP_ORA_ZP, ISA_OP_ORA_ZPX, ISA_OP_PHA, ISA_OP_PHP,
+    ISA_OP_PLA, ISA_OP_PLP, ISA_OP_ROL_A, ISA_OP_ROL_ABS, ISA_OP_ROL_ABSX, ISA_OP_ROL_ZP,
+    ISA_OP_ROL_ZPX, ISA_OP_ROR_A, ISA_OP_ROR_ABS, ISA_OP_ROR_ABSX, ISA_OP_ROR_ZP, ISA_OP_ROR_ZPX,
+    ISA_OP_RTI, ISA_OP_RTS, ISA_OP_SBC_ABS, ISA_OP_SBC_ABSX, ISA_OP_SBC_ABSY, ISA_OP_SBC_I,
+    ISA_OP_SBC_INDX, ISA_OP_SBC_INDY, ISA_OP_SBC_ZP, ISA_OP_SBC_ZPX, ISA_OP_SEC, ISA_OP_SED,
+    ISA_OP_SEI, ISA_OP_STA_ABS, ISA_OP_STA_ABSX, ISA_OP_STA_ABSY, ISA_OP_STA_INDX, ISA_OP_STA_INDY,
+    ISA_OP_STA_ZP, ISA_OP_STA_ZPX, ISA_OP_STX_ABS, ISA_OP_STX_ZP, ISA_OP_STX_ZPY, ISA_OP_STY_ABS,
+    ISA_OP_STY_ZP, ISA_OP_STY_ZPX, ISA_OP_TAX, ISA_OP_TAY, ISA_OP_TSX, ISA_OP_TXA, ISA_OP_TXS,
+    ISA_OP_TYA,
+};
 use crate::op_info::OpInfo;
 use crate::operation::Operation;
 use crate::operation::Operation::*;
 
-
 pub fn INSTRUCTION_CYCLES(instruction: u8) -> u8 {
     INSTRUCTION_TABLE[instruction as usize].unwrap().cycles
 }
@@ -723,7 +749,7 @@ pub const INSTRUCTION_TABLE: [Option<OpInfo>; 256] = {
         operation: Operation::ROR,
         mode: AddressMode::Accumulator,
         length: 1,
-        cycles: 2
+        cycles: 2,
     });
     table[ISA_OP_ROR_ZP as usize] = Some(OpInfo {
         operation: Operation::ROR,
@@ -996,4 +1022,4 @@ mod test {
             defined_count
         );
     }
-}
+}

core/src/lib.rs

@@ -1,11 +1,11 @@
-pub mod periph;
+pub mod computers;
 pub mod address_mode;
-pub mod mos6502cpu;
-pub mod instruction;
-pub mod mos6502flags;
 pub mod constants;
-pub mod operation;
+pub mod instruction;
+pub mod instruction_table;
+pub mod mos6502cpu;
+pub mod mos6502flags;
 pub mod op_info;
 pub mod operand;
-pub mod instruction_table;
-pub mod computers;
+pub mod operation;
+pub mod periph;

core/src/mos6502cpu/cpu.rs

@@ -1,44 +1,45 @@
-use log::trace;
 use crate::address_mode::AddressMode;
 use crate::constants::constants_isa_op::ISA_OP_NOP;
+use crate::constants::constants_system::*;
 use crate::instruction::Instruction;
-use crate::mos6502flags::{Mos6502Flag, Mos6502Flags};
+use crate::instruction_table::INSTRUCTION_TABLE;
 use crate::mos6502flags::Mos6502Flag::*;
+use crate::mos6502flags::{Mos6502Flag, Mos6502Flags};
 use crate::op_info::OpInfo;
 use crate::operand::Operand;
 use crate::operation::Operation;
-use crate::constants::constants_system::*;
-use crate::instruction_table::INSTRUCTION_TABLE;
+use log::trace;
 
 pub struct Mos6502Cpu {
-    memory: [u8; SIZE_64KB],
+    pub(crate) memory: [u8; SIZE_64KB],
     /// accumulator
-    a: u8,
+    pub(crate) a: u8,
     /// x register
-    x: u8,
+    pub(crate) x: u8,
     /// y register
-    y: u8,
+    pub(crate) y: u8,
     /// cpu flags
-    flags: Mos6502Flags,
+    pub(crate) flags: Mos6502Flags,
     /// program counter
     pub pc: u16,
     /// stack offset
-    s: u8,
+    pub(crate) s: u8,
     pub microcode_step: u8,
-    address_bus: u16,
-    data_bus: u8,
-    ir: Instruction, // Instruction Register
-    oi: OpInfo,
-    has_reset: bool,
-    iv: u16, // Interrupt Vector
-    cycle_carry: u16, // Value to hold between microsteps
-    ir_bytes: [u8; 4],
+    pub(crate) address_bus: u16,
+    pub(crate) data_bus: u8,
+    pub(crate) ir: Instruction, // Instruction Register
+    pub(crate) oi: OpInfo,
+    pub(crate) has_reset: bool,
+    pub(crate) iv: u16,          // Interrupt Vector
+    pub(crate) cycle_carry: u16, // Value to hold between microsteps
+    pub(crate) ir_bytes: [u8; 4],
     /// CPU Read signal
-    pub read_signal: bool
+    pub read_signal: bool,
+    pub(crate) reset_vector: u16,
+    pub(crate) int_vector: u16
 }
 
 impl Mos6502Cpu {
-
     /// set_data_bus
     ///
     /// Sets data on the data bus.
@@ -71,7 +72,9 @@ impl Default for Mos6502Cpu {
             iv: 0xfffe,
             cycle_carry: 0x0000,
             ir_bytes: [0x00; 4],
-            read_signal: true
+            read_signal: true,
+            reset_vector: 0x0000,
+            int_vector: 0x0000
         };
         working.reset_cpu();
         working
@@ -87,46 +90,27 @@ impl Mos6502Cpu {
         self.data_bus
     }
 
-    pub fn new() -> Mos6502Cpu {
-        let array = [0x00u8; SIZE_64KB];
-        let mut working = Mos6502Cpu {
-            memory: array,
-            ir_bytes: [0x00; 4],
-            ..Default::default()
-        };
-        working.reset_cpu();
-        working
-    }
-
-    fn reset_cpu(&mut self) {
-        // self = &mut Mos6502Cpu::default();
-        println!("Should tick 7 times.");
-        // read the value at 0xfffc 0xfffd for our reset vector.
-        // read the value at 0xfffe 0xffff for our int vector
-        self.pc = self.read_word(&OFFSET_RESET_VECTOR);
-        println!("READ FROM {OFFSET_RESET_VECTOR} AND GOT {}", self.pc);
-        self.iv = self.read_word(&OFFSET_INT_VECTOR);
-        self.address_bus = self.pc;
-        self.read_signal = true;
-        println!("PC and IV are now set from ROM addresses / AB = {:016b}", self.address_bus);
-    }
-
-    fn read_word(&self, offset: &u16) -> u16 {
-        println!("READING OFFSET 0x{offset:04x} and 0x{:04x}", offset + 1);
-        let low = self.memory[*offset as usize];
-        let high = self.memory[*offset as usize + 1];
-        println!("LOW = 0x{low:02x} HIGH = 0x{high:02x}");
-        let result = (high as u16) << 8 | low as u16;
-        // println!("MEMORY: {:?}", self.memory);
-        println!("READ {result:04x}");
-        result
-    }
+    //
+    // fn read_word(&self, offset: &u16) -> u16 {
+    //     println!("READING OFFSET 0x{offset:04x} and 0x{:04x}", offset + 1);
+    //     let low = self.memory[*offset as usize];
+    //     let high = self.memory[*offset as usize + 1];
+    //     println!("LOW = 0x{low:02x} HIGH = 0x{high:02x}");
+    //     let result = (high as u16) << 8 | low as u16;
+    //     // println!("MEMORY: {:?}", self.memory);
+    //     println!("READ {result:04x}");
+    //     result
+    // }
 
     pub fn peek_flag(&self, flag_to_read: Mos6502Flag) -> bool {
         self.flags.flag(flag_to_read)
     }
     pub fn poke_flag(&mut self, flag_to_set: Mos6502Flag, new_value: bool) {
-        if new_value { self.flags.set_flag(flag_to_set) } else { self.flags.clear_flag(flag_to_set) }
+        if new_value {
+            self.flags.set_flag(flag_to_set)
+        } else {
+            self.flags.clear_flag(flag_to_set)
+        }
     }
 
     pub fn peek(&self, offset: u16) -> u8 {
@@ -139,16 +123,16 @@ impl Mos6502Cpu {
     }
 
     pub fn peek_a(&self) -> u8 {
+        println!("Readding register A => 0x{:02x}", self.a);
         self.a
     }
     pub fn poke_a(&mut self, new_a: u8) {
-
-    println!("Updating register A from [{}] to [{}]", self.a, new_a);
-
-    self.a = new_a;
+        println!("Updating register A from [{}] to [{}]", self.a, new_a);
+        self.a = new_a;
     }
 
     pub fn peek_x(&self) -> u8 {
+        println!("Readding register X => 0x{}", self.x);
         self.x
     }
 
@@ -175,7 +159,6 @@ impl Mos6502Cpu {
 
     /// Ticks the CPU
     pub fn tick(&mut self) {
-
         println!("PREPARiNG TO TICK CPU AT PC 0x{:04x}", self.pc);
         if self.microcode_step == 0 {
             println!("OUT OF MICROSTEPS.  Decoding the next instruction");
@@ -190,28 +173,27 @@ impl Mos6502Cpu {
             // set the counter to the number of steps left
         } else {
             // run 1 microcode step
-            println!("Microstep {}/{} for {:?}", self.microcode_step, self.oi.cycles,  self.ir.op);
+            println!(
+                "Microstep {}/{} for {:?}",
+                self.microcode_step, self.oi.cycles, self.ir.op
+            );
             match self.ir.op {
-                Operation::ADC => {
-                    match self.microcode_step {
-                        1 => {
-                            match self.ir.mode {
-                                AddressMode::Immediate => {}
-                                AddressMode::ZeroPage => {}
-                                AddressMode::ZeroPageX => {}
-                                AddressMode::Absolute => {}
-                                AddressMode::AbsoluteX => {}
-                                AddressMode::AbsoluteY => {}
-                                AddressMode::Indirect => {}
-                                AddressMode::IndirectX => {}
-                                AddressMode::IndirectY => {}
-                                _ => {}
-                            }
-                        },
-                        2 => {},
+                Operation::ADC => match self.microcode_step {
+                    1 => match self.ir.mode {
+                        AddressMode::Immediate => {}
+                        AddressMode::ZeroPage => {}
+                        AddressMode::ZeroPageX => {}
+                        AddressMode::Absolute => {}
+                        AddressMode::AbsoluteX => {}
+                        AddressMode::AbsoluteY => {}
+                        AddressMode::Indirect => {}
+                        AddressMode::IndirectX => {}
+                        AddressMode::IndirectY => {}
                         _ => {}
-                    }
-                }
+                    },
+                    2 => {}
+                    _ => {}
+                },
                 Operation::AND => {}
                 Operation::ASL => {}
                 Operation::BCC => {}
@@ -247,10 +229,8 @@ impl Mos6502Cpu {
                                 AddressMode::ZeroPage => {
                                     // read from
                                     let offset = match self.ir.operand {
-                                        Operand::Byte(z) => {
-                                            z
-                                        }
-                                        _ => { 0x00 }
+                                        Operand::Byte(z) => z,
+                                        _ => 0x00,
                                     };
                                     trace!("READING FROM MEMORY AT 0x{offset:04x}");
                                     self.memory[offset as usize]
@@ -258,37 +238,29 @@ impl Mos6502Cpu {
                                 }
                                 AddressMode::ZeroPageX => {
                                     let offset = match self.ir.operand {
-                                        Operand::Byte(z) => {
-                                            z
-                                        }
-                                        _ => { 0x00 }
+                                        Operand::Byte(z) => z,
+                                        _ => 0x00,
                                     };
                                     // self.memory.peek(offset + self.x);
                                     self.memory[offset as usize]
                                 }
                                 AddressMode::Absolute => {
                                     let offset = match self.ir.operand {
-                                        Operand::Word(offset) => {
-                                            offset
-                                        }
-                                        _ => { 0x00 }
+                                        Operand::Word(offset) => offset,
+                                        _ => 0x00,
                                     };
                                     // self.memory.peek(offset)
                                     self.memory[offset as usize]
                                 }
                                 AddressMode::AbsoluteX => {
                                     let offset = match self.ir.operand {
-                                        Operand::Word(offset) => {
-                                            offset
-                                        }
-                                        _ => { 0x00 }
+                                        Operand::Word(offset) => offset,
+                                        _ => 0x00,
                                     };
                                     // self.memory.peek(offset + self.x);
                                     self.memory[offset as usize]
                                 }
-                                _ => {
-                                    0x00
-                                }
+                                _ => 0x00,
                             };
                         }
                         // DEC write memory
@@ -310,8 +282,8 @@ impl Mos6502Cpu {
                         (self.y, _) = self.y.overflowing_sub(1);
                     }
                 }
-                Operation::EOR => { }
-                Operation::INC => { }
+                Operation::EOR => {}
+                Operation::INC => {}
                 Operation::INX => {
                     if self.microcode_step == 1 {
                         let (new_x, new_carry) = self.x.overflowing_add(1);
@@ -328,75 +300,67 @@ impl Mos6502Cpu {
                         self.poke_flag(Carry, new_carry);
                         self.address_bus = self.pc;
                         self.data_bus = 0x00;
-                    }                }
-                Operation::JMP => {
-                    match self.ir.operand {
-                        Operand::Word(offset) => {
-                            self.pc = offset;
-                            self.address_bus = self.pc;
-                            self.data_bus = 0x00;
-                        }
-                        _ => {}
                     }
                 }
+                Operation::JMP => match self.ir.operand {
+                    Operand::Word(offset) => {
+                        self.pc = offset;
+                        self.address_bus = self.pc;
+                        self.data_bus = 0x00;
+                    }
+                    _ => {}
+                },
                 Operation::JSR => {
                     // push pc to stack.
                     // jump to the subroutine.
                 }
-                Operation::LDA => {
-                    match self.oi.mode {
-                        AddressMode::Immediate => {
-                            match self.ir.operand {
-                                Operand::Byte(value) => {
-                                    println!("Loading 0x{value:02x} ({value}) into A");
-                                    self.a = value;
-                                }
-                                _ => {}
-                            }
+                Operation::LDA => match self.oi.mode {
+                    AddressMode::Immediate => match self.ir.operand {
+                        Operand::Byte(value) => {
+                            println!("Loading 0x{value:02x} ({value}) into A");
+                            self.a = value;
                         }
-                        AddressMode::ZeroPage => {
-                            match self.ir.operand {
-                                Operand::Byte(value) => {
-                                    println!("Loading from zero page at 0x{value:02x} ({value})");
-                                    self.a = self.memory[value as usize];
-                                }
-                                _ => {}
-                            }
+                        _ => {}
+                    },
+                    AddressMode::ZeroPage => match self.ir.operand {
+                        Operand::Byte(value) => {
+                            println!("Loading from zero page at 0x{value:02x} ({value})");
+                            self.a = self.memory[value as usize];
                         }
-                        AddressMode::ZeroPageX => {
-                            match self.ir.operand {
-                                Operand::Byte(value) => {
-                                    let x_offset = self.x;
-                                    self.a = self.memory[(value + x_offset) as usize];
-                                }
-                                _ => {}
-                            }
+                        _ => {}
+                    },
+                    AddressMode::ZeroPageX => match self.ir.operand {
+                        Operand::Byte(value) => {
+                            let x_offset = self.x;
+                            self.a = self.memory[(value + x_offset) as usize];
                         }
-                        AddressMode::Absolute => {
-                            if let Operand::Word(offset) = self.ir.operand {
-                                println!("Loading from absolute address 0x{offset:04x}");
-                                self.a = self.memory[offset as usize];
-                            }
-
-                        }
-                        AddressMode::AbsoluteX => {
-                            if let Operand::Word(offset) = self.ir.operand {
-                                self.a = self.memory[(offset + self.x as u16) as usize];
-                            }
-                        }
-                        AddressMode::AbsoluteY => {
-                            if let Operand::Word(offset) = self.ir.operand {
-                                self.a = self.memory[(offset + self.y as u16) as usize];
-                            }
-                        }
-                        AddressMode::Indirect => {}
-                        AddressMode::IndirectX => {}
-                        AddressMode::IndirectY => {}
-                        _ => {
-                            println!("INVALID ADDRESS MODE FOR LDA");
+                        _ => {}
+                    },
+                    AddressMode::Absolute => {
+                        if let Operand::Word(offset) = self.ir.operand {
+                            println!("Loading from absolute address 0x{offset:04x}");
+                            self.a = self.memory[offset as usize];
                         }
                     }
-                }
+                    AddressMode::AbsoluteX => {
+                        if let Operand::Word(offset) = self.ir.operand {
+                            self.a = self.memory[(offset + self.x as u16) as usize];
+                        }
+                    }
+                    AddressMode::AbsoluteY => {
+                        if let Operand::Word(offset) = self.ir.operand {
+                            let real_offset = offset + self.y as u16;
+                            println!("offset: {offset:04x} + {:02x}", self.y);
+                            self.a = self.memory[(offset + self.y as u16) as usize];
+                        }
+                    }
+                    AddressMode::Indirect => {}
+                    AddressMode::IndirectX => {}
+                    AddressMode::IndirectY => {}
+                    _ => {
+                        println!("INVALID ADDRESS MODE FOR LDA");
+                    }
+                },
                 Operation::LDX => {}
                 Operation::LDY => {}
                 Operation::LSR => {}
@@ -501,13 +465,11 @@ impl Mos6502Cpu {
                 Operation::TAY => {
                     self.y = self.a;
                 }
-                Operation::TSX => {
-                }
+                Operation::TSX => {}
                 Operation::TXA => {
                     self.a = self.x;
                 }
-                Operation::TXS => {
-                }
+                Operation::TXS => {}
                 Operation::TYA => {
                     self.y = self.a;
                 }
@@ -515,27 +477,13 @@ impl Mos6502Cpu {
             self.microcode_step -= 1;
         }
     }
-
-    pub fn dump(&self) {
-        println!("CPU State: PC: {:04x} / A: {:02x} / X: {:02x} / Y: {:02x} / ADDRESS: {:04x} / DATA: {:02x} / MICROSTEPS: {:02x} / S: {}",
-            self.pc, self.a, self.x, self.y, self.address_bus, self.data_bus, self.microcode_step, self.flags.dump());
-    }
-
-    /// dump_data
-    ///
-    /// returns
-    ///     PC, A, X, Y, Address_Bus, Data_Bus, Microcode_Step
-    pub fn dump_data(&self) -> ( u16, u8, u8, u8, u16, u8, u8) {
-        (self.pc, self.a, self.x, self.y, self.address_bus, self.data_bus, self.microcode_step)
-    }
-
 }
 
 #[cfg(test)]
 mod test {
+    use super::*;
     use crate::constants::constants_isa_op::*;
     use crate::instruction_table::{INSTRUCTION_CYCLES, INSTRUCTION_TABLE};
-    use super::*;
 
     #[test]
     fn clc() {
@@ -548,7 +496,9 @@ mod test {
         cpu.pc = 0x6000;
 
         // Tick the CPU through the instruction
-        for _ in 0..INSTRUCTION_TABLE[ISA_OP_CLC as usize].unwrap().cycles { cpu.tick(); }
+        for _ in 0..INSTRUCTION_CYCLES(ISA_OP_CLC) {
+            cpu.tick();
+        }
 
         assert!(!cpu.peek_flag(Carry));
     }
@@ -560,7 +510,9 @@ mod test {
         cpu.memory[0x6000] = ISA_OP_CLD;
         cpu.pc = 0x6000;
 
-        for _ in 0..INSTRUCTION_TABLE[ISA_OP_CLD as usize].unwrap().cycles { cpu.tick(); }
+        for _ in 0..INSTRUCTION_CYCLES(ISA_OP_CLD) {
+            cpu.tick();
+        }
 
         assert!(!cpu.peek_flag(Decimal));
     }
@@ -572,10 +524,11 @@ mod test {
         cpu.memory[0x6000] = ISA_OP_CLI;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_CLI) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_CLI) {
+            cpu.tick();
+        }
 
         assert!(!cpu.peek_flag(Interrupt));
-
     }
 
     #[test]
@@ -585,7 +538,9 @@ mod test {
         cpu.memory[0x6000] = ISA_OP_CLV;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_CLV) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_CLV) {
+            cpu.tick();
+        }
 
         assert!(!cpu.peek_flag(Overflow));
     }
@@ -597,7 +552,9 @@ mod test {
         cpu.memory[0x6001] = 0xab;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_I) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_I) {
+            cpu.tick();
+        }
 
         assert_eq!(cpu.a, 0xab);
     }
@@ -611,7 +568,9 @@ mod test {
         cpu.memory[0x00ac] = 0xbe;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ZX) { cpu.tick(); };
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ZX) {
+            cpu.tick();
+        }
 
         // println!("MEMORY AT 0x00aa, ab, ac, ad, ae -> {:02x} {:02x} {:02x} {:02x} {:02x}", cpu.memory[0x00aa], cpu.memory[0x00ab], cpu.memory[0x00ac], cpu.memory[0x00ad], cpu.memory[0x00ae]);
         // cpu.dump();
@@ -630,7 +589,9 @@ mod test {
         cpu.memory[0x00ab] = 0xbe;
         cpu.pc = 0x6000;
 
-        for _ in 0..INSTRUCTION_CYCLES(ISA_OP_LDA_Z) { cpu.tick(); }
+        for _ in 0..INSTRUCTION_CYCLES(ISA_OP_LDA_Z) {
+            cpu.tick();
+        }
 
         assert_eq!(cpu.a, 0xbe);
     }
@@ -644,7 +605,9 @@ mod test {
         cpu.memory[0x0eef] = 0xab;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ABS) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ABS) {
+            cpu.tick();
+        }
 
         assert_eq!(cpu.a, 0xab);
     }
@@ -659,7 +622,9 @@ mod test {
         cpu.memory[0x0ef0] = 0xab;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ABSX) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ABSX) {
+            cpu.tick();
+        }
 
         assert_eq!(cpu.a, 0xab);
     }
@@ -669,12 +634,14 @@ mod test {
         let mut cpu = Mos6502Cpu::default();
         cpu.memory[0x6000] = ISA_OP_LDA_ABSY;
         cpu.memory[0x6001] = 0xef;
-        cpu.memory[0x6002] = 0xbe;
+        cpu.memory[0x6002] = 0x0e;
         cpu.poke_y(0x01);
         cpu.memory[0x0ef0] = 0xab;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ABSY) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_LDA_ABSY) {
+            cpu.tick();
+        }
 
         assert_eq!(cpu.a, 0xab);
     }
@@ -687,9 +654,13 @@ mod test {
         cpu.memory[0x6001] = ISA_OP_INX;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_DEX) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_DEX) {
+            cpu.tick();
+        }
         assert_eq!(0xaa, cpu.x);
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_INX) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_INX) {
+            cpu.tick();
+        }
         assert_eq!(0xab, cpu.x);
     }
 
@@ -701,9 +672,13 @@ mod test {
         cpu.memory[0x6001] = ISA_OP_INY;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_DEY) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_DEY) {
+            cpu.tick();
+        }
         assert_eq!(0xaa, cpu.peek_y());
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_INY) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_INY) {
+            cpu.tick();
+        }
         assert_eq!(0xab, cpu.peek_y());
     }
 
@@ -715,9 +690,28 @@ mod test {
         cpu.memory[0x6001] = ISA_OP_ROR_A;
         cpu.pc = 0x6000;
 
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_ROL_A) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_ROL_A) {
+            cpu.tick();
+        }
         assert_eq!(cpu.peek_a(), 0b0101_0101);
-        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_ROR_A) { cpu.tick(); }
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_ROR_A) {
+            cpu.tick();
+        }
         assert_eq!(cpu.peek_a(), 0b1010_1010);
     }
+
+    #[test]
+    fn rol_zp_ror_zp() {
+        let mut cpu = Mos6502Cpu::default();
+        cpu.memory[0x00ab] = 0b0101_0101;
+        cpu.memory[0x6000] = ISA_OP_ROL_ZP;
+        cpu.memory[0x6001] = 0xab;
+        cpu.pc = 0x6000;
+
+        for _ in 0..=INSTRUCTION_CYCLES(ISA_OP_ROL_ZP) {
+            cpu.tick();
+        }
+
+        assert_eq!(cpu.memory[0xab], 0b1010_1010);;
+    }
 }

core/src/mos6502cpu/dbg.rs

@@ -0,0 +1,35 @@
+use crate::mos6502cpu::cpu::Mos6502Cpu;
+
+impl Mos6502Cpu {
+    /// dump_data
+    ///
+    /// returns
+    ///     PC, A, X, Y, Address_Bus, Data_Bus, Microcode_Step
+    pub fn dump_data(&self) -> (u16, u8, u8, u8, u16, u8, u8, u16, u16) {
+        (
+            self.pc,
+            self.a,
+            self.x,
+            self.y,
+            self.address_bus,
+            self.data_bus,
+            self.microcode_step,
+            self.reset_vector,
+            self.int_vector
+        )
+    }
+
+    pub fn dump(&self) {
+        println!(
+            "CPU State: PC: {:04x} / A: {:02x} / X: {:02x} / Y: {:02x} / ADDRESS: {:04x} / DATA: {:02x} / MICROSTEPS: {:02x} / S: {}",
+            self.pc,
+            self.a,
+            self.x,
+            self.y,
+            self.address_bus,
+            self.data_bus,
+            self.microcode_step,
+            self.flags.dump()
+        );
+    }
+}

core/src/mos6502cpu/mod.rs

@@ -0,0 +1,6 @@
+pub mod cpu;
+pub mod new;
+
+pub mod tick2;
+mod dbg;
+mod tick_stages;

core/src/mos6502cpu/new.rs

@@ -0,0 +1,26 @@
+use crate::constants::constants_system::{OFFSET_RESET_VECTOR, SIZE_64KB};
+use crate::mos6502cpu::cpu::Mos6502Cpu;
+
+impl Mos6502Cpu {
+    pub fn new() -> Mos6502Cpu {
+        let array = [0x00u8; SIZE_64KB];
+        let mut working = Mos6502Cpu {
+            memory: array,
+            ir_bytes: [0x00; 4],
+            ..Default::default()
+        };
+        working.reset_cpu();
+        working
+    }
+
+
+    pub(crate) fn reset_cpu(&mut self) {
+        self.microcode_step = 7 + 4;
+        // self = &mut Mos6502Cpu::default();
+        println!("Should tick 7 times, then 4 cycles to read the reset and int vectors.");
+        // read the value at 0xfffc 0xfffd for our reset vector.
+        // read the value at 0xfffe 0xffff for our int vector
+    }
+
+
+}

core/src/mos6502cpu/tick2.rs

@@ -0,0 +1,64 @@
+use crate::constants::constants_system::{OFFSET_INT_VECTOR, OFFSET_RESET_VECTOR};
+use crate::mos6502cpu::cpu::Mos6502Cpu;
+
+impl Mos6502Cpu {
+    /// AccurateTick
+    ///
+    /// In: address_bus  > Address of data operationm
+    ///     data_bus     > Data read or written
+    /// State:
+    ///     read_bus     > Flag for if cpu is reading or writing the data bus
+    ///     cycle_step   > Index for what step of the Decode->Load->Execute cycle we are in
+    /// Out: address_bus > address for operation
+    ///      data_bus    > data for the operation
+    ///      read_bus    > lets rest of the computer know if the CPU is reading from the address
+    ///                   provided or if we are writing to the address
+    pub fn tick2(&mut self, address_bus: u16, data_bus: u8) -> (u16, u8, bool) {
+        if self.has_reset {
+            // we have completed the reset cycle
+            if self.read_signal {
+                // we should see new data in the data_bus for us
+                let read_data = data_bus;
+            } else {
+                // we are writing to the bus.
+            }
+        } else {
+            println!("Reset microstep {}", self.microcode_step);            
+            // we need to do the reset steps
+            // reduce the number of remaining microsteps
+            self.read_signal = true;
+            match self.microcode_step {
+                4 => {
+                    // read first byte of reset vector
+                    self.address_bus = OFFSET_RESET_VECTOR;
+                }
+                3 => {
+                    // at this point data holds the upper byte of our reset vector
+                    self.reset_vector = (data_bus as u16) << 8;
+                    // read secondd byte of reset vector
+                    self.address_bus = OFFSET_RESET_VECTOR + 1;
+                }
+                2 => {
+                    self.reset_vector |= data_bus as u16;
+                    println!("Loaded reset vector of 0x{:04x}", self.reset_vector);
+                    // read first byte of interrupt vector
+                    self.address_bus = OFFSET_INT_VECTOR;
+                }
+                1 => {
+                    // read second byte of interrupt vector
+                    self.address_bus = OFFSET_INT_VECTOR + 1;
+                }
+                0 => {
+                    self.int_vector |= data_bus as u16;
+                    println!("Loaded interrupt vector of 0x{:04x}", self.int_vector);
+                    self.pc = self.reset_vector;
+                    println!("Set PC to Reset Vector.  Giddy-up!");
+                }
+                _ => {
+                }
+            }
+            self.microcode_step -= 1;
+        }
+        (self.address_bus, self.data_bus, self.read_signal)
+    }
+}

core/src/mos6502cpu/tick_stages.rs

@@ -0,0 +1,19 @@
+
+/// Mos6502TickStates
+/// 
+/// The set of what a tick can be doing
+///
+enum Mos6502TickStates {
+    /// Loading the first byte into the IR
+    LoadingInstruction,
+    /// Loading an 8 bit parameter
+    Loading8BitParameter,
+    /// Loading the MSB 8 bits
+    Loading16BitParameter1,
+    /// Loading the LSB 8 bits
+    Loading16BitParameter2,
+    /// Stalling for accurate emulation
+    Stall(u8),
+    /// Completed the instruction
+    Complete
+}

core/src/mos6502flags.rs

@@ -1,4 +1,6 @@
-use crate::mos6502flags::Mos6502Flag::{Break, Carry, Decimal, Interrupt, Negative, Overflow, Zero};
+use crate::mos6502flags::Mos6502Flag::{
+    Break, Carry, Decimal, Interrupt, Negative, Overflow, Zero,
+};
 
 pub const BIT_NEGATIVE: u8 = 7;
 pub const BIT_OVERFLOW: u8 = 6;
@@ -59,7 +61,7 @@ impl Mos6502Flag {
             Decimal => BIT_DECIMAL,
             Break => BIT_BREAK,
             Overflow => BIT_OVERFLOW,
-            Negative => BIT_NEGATIVE
+            Negative => BIT_NEGATIVE,
         }
     }
 }
@@ -77,14 +79,15 @@ pub struct Mos6502Flags {
 
 impl Mos6502Flags {
     pub fn dump(&self) -> String {
-        format!("{}{}{}{}{}{}{}",
-                if self.carry { 'C' } else { 'c' },
-                if self.zero { 'Z' } else { 'z' },
-                if self.interrupt { 'I' } else { 'i' },
-                if self.decimal { 'D' } else { 'd' },
-                if self.break_flag { 'B' } else { 'b' },
-                if self.overflow { 'O' } else { 'o' },
-                if self.negative { 'N' } else { 'n' }
+        format!(
+            "{}{}{}{}{}{}{}",
+            if self.carry { 'C' } else { 'c' },
+            if self.zero { 'Z' } else { 'z' },
+            if self.interrupt { 'I' } else { 'i' },
+            if self.decimal { 'D' } else { 'd' },
+            if self.break_flag { 'B' } else { 'b' },
+            if self.overflow { 'O' } else { 'o' },
+            if self.negative { 'N' } else { 'n' }
         )
     }
 }
@@ -113,7 +116,8 @@ impl Mos6502Flags {
             Break => self.break_flag = false,
             Overflow => self.overflow = false,
             Negative => self.negative = false,
-        }    }
+        }
+    }
 
     fn change_flag(&mut self, flag_to_change: Mos6502Flag, new_value: bool) {
         if new_value {
@@ -139,25 +143,37 @@ impl Mos6502Flags {
     pub fn as_byte(&self) -> u8 {
         let mut working = 0x00;
 
-        if self.flag(Negative)  { working += 1 << Negative.index(); }
-        if self.flag(Overflow)  { working += 1 << Overflow.index(); }
-                                  working += 1 << 5; // Always Set
-        if self.flag(Break)     { working += 1 << Break.index(); }
-        if self.flag(Decimal)   { working += 1 << Decimal.index(); }
-        if self.flag(Interrupt) { working += 1 << Interrupt.index(); }
-        if self.flag(Zero)      { working += 1 << Zero.index(); }
-        if self.flag(Carry)     { working += 1 << Carry.index(); }
+        if self.flag(Negative) {
+            working += 1 << Negative.index();
+        }
+        if self.flag(Overflow) {
+            working += 1 << Overflow.index();
+        }
+        working += 1 << 5; // Always Set
+        if self.flag(Break) {
+            working += 1 << Break.index();
+        }
+        if self.flag(Decimal) {
+            working += 1 << Decimal.index();
+        }
+        if self.flag(Interrupt) {
+            working += 1 << Interrupt.index();
+        }
+        if self.flag(Zero) {
+            working += 1 << Zero.index();
+        }
+        if self.flag(Carry) {
+            working += 1 << Carry.index();
+        }
 
         working
     }
 
-
-
     pub fn from_byte(src: u8) -> Self {
         let mut working = Self::default();
 
         working.change_flag(Negative, Self::bit(src, Negative.index()));
-        working.change_flag(Overflow,  Self::bit(src, Overflow.index()));
+        working.change_flag(Overflow, Self::bit(src, Overflow.index()));
         working.change_flag(Break, Self::bit(src, Break.index()));
         working.change_flag(Decimal, Self::bit(src, Decimal.index()));
         working.change_flag(Interrupt, Self::bit(src, Interrupt.index()));
@@ -182,14 +198,15 @@ impl Mos6502Flags {
     }
 }
 
-
 #[cfg(test)]
 mod test {
 
     use super::*;
 
     #[test]
-    fn smoke() { assert!(true); }
+    fn smoke() {
+        assert!(true);
+    }
 
     #[test]
     fn sanity() {

core/src/operation.rs

@@ -356,5 +356,4 @@ pub enum Operation {
     ///
     /// Addressing Modes: Implied
     TYA,
-
-}
+}

core/src/periph/at28c256/default.rs

@@ -6,10 +6,10 @@ impl Default for At28C256 {
     fn default() -> Self {
         let vec = vec![0xea; SIZE_32KB];
         let boxed_slice: Box<[u8]> = vec.into_boxed_slice();
-        let boxed_array: Box<[u8; SIZE_32KB]> = boxed_slice.try_into().expect("Failed to convert Vec to boxed array");
-        At28C256 {
-            data: boxed_array,
-        }
+        let boxed_array: Box<[u8; SIZE_32KB]> = boxed_slice
+            .try_into()
+            .expect("Failed to convert Vec to boxed array");
+        At28C256 { data: boxed_array }
     }
 }
 
@@ -18,5 +18,7 @@ mod test {
     use super::*;
 
     #[test]
-    fn smoke() { assert!(true); }
+    fn smoke() {
+        assert!(true);
+    }
 }

core/src/periph/at28c256/mod.rs

@@ -1,9 +1,10 @@
-mod default;
-mod rom_chip;
+pub mod default;
+pub mod rom_chip;
+pub mod tick;
 
-use std::io::Read;
 use crate::constants::constants_system::SIZE_32KB;
 use crate::periph::rom_chip::RomChip;
+use std::io::Read;
 
 /// At28C256
 ///
@@ -25,8 +26,8 @@ impl At28C256 {
 
 #[cfg(test)]
 mod test {
-    use crate::constants::constants_system::SIZE_1KB;
     use super::*;
+    use crate::constants::constants_system::SIZE_1KB;
 
     #[test]
     fn smoke() {
@@ -40,9 +41,8 @@ mod test {
             data.data[i] = 0xea;
         }
         for offset in 0..SIZE_32KB {
-            if offset.is_multiple_of(SIZE_1KB) {
-            };
-           assert_eq!(0xea, data.read(&(offset as u16)));
+            if offset.is_multiple_of(SIZE_1KB) {};
+            assert_eq!(0xea, data.read(&(offset as u16)));
         }
     }
 }

core/src/periph/at28c256/rom_chip.rs

@@ -3,7 +3,6 @@ use crate::periph::at28c256::At28C256;
 use crate::periph::rom_chip::RomChip;
 
 impl RomChip for At28C256 {
-
     fn read(&self, offset: &u16) -> u8 {
         self.data[*offset as usize]
     }
@@ -21,7 +20,7 @@ mod test {
     use super::*;
 
     #[test]
-    fn smoke() { assert!(true); }
-
-
-}
+    fn smoke() {
+        assert!(true);
+    }
+}

core/src/periph/at28c256/tick.rs

@@ -0,0 +1,31 @@
+use crate::periph::at28c256::At28C256;
+use crate::periph::hm62256::Hm62256;
+
+impl At28C256 {
+    fn tick(&mut self, address_bus: u16, data_bus: u8, read_mode: bool) -> (u16, u8) {
+        if !read_mode {
+            // has to be read mode.  its a rom.
+            return (address_bus, data_bus)
+        }
+        (address_bus, self.data[address_bus as usize])
+    }
+}
+
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn smoke() { assert!(true); }
+
+    #[test]
+    fn write_to_memory_read_back_works_at_0() {
+        let mut rom = At28C256::default();
+
+        rom.tick(0x0000, 0xab, false);
+        let (_, new_data) = rom.tick(0x0000, 0x00, true);
+
+        assert_eq!(new_data, 0xab);
+    }
+}

core/src/periph/hm62256/mod.rs

@@ -1,55 +1,40 @@
 // HM62256 Static Ram
 
-use log::debug;
+pub mod ramchip;
+pub mod romchip;
+pub mod tick;
+
 use crate::constants::constants_system::SIZE_32KB;
 use crate::periph::ram_chip::RamChip;
 use crate::periph::rom_chip::RomChip;
-
+use log::debug;
 pub struct Hm62256 {
     pub(crate) base_offset: u16,
-    pub(crate) data: Box<[u8]>
+    pub(crate) data: Box<[u8]>,
 }
 
 impl Default for Hm62256 {
     fn default() -> Self {
         let vec = vec![0x00; SIZE_32KB];
         let boxed_slice: Box<[u8]> = vec.into_boxed_slice();
-        let boxed_array: Box<[u8; SIZE_32KB]> = boxed_slice.try_into().expect("Unable to box the ram");
+        let boxed_array: Box<[u8; SIZE_32KB]> =
+            boxed_slice.try_into().expect("Unable to box the ram");
         Hm62256 {
             base_offset: 0x0000,
-            data: boxed_array
+            data: boxed_array,
         }
     }
 }
 
-impl RomChip for Hm62256 {
-    fn read(&self, offset: &u16) -> u8 {
-        // loops memory around past 32k
-        let effective = *offset as i32  % SIZE_32KB as i32;
-        self.data[effective as usize]
-    }
-
-    fn program(_: &[u8; SIZE_32KB]) -> Box<Self> {
-        debug!("Dont program ram.");
-        Hm62256::default().into()
-    }
-}
-
-impl RamChip for Hm62256 {
-    fn write(&mut self, offset: &u16, value: &u8) {
-        let effective = *offset as i32  % SIZE_32KB as i32;
-        println!("Writing at E[{effective:04x}] / O[{offset:04x}]");
-        self.data[effective as usize] = *value;
-    }
-}
-
 #[cfg(test)]
 mod test {
-    use rand::random;
     use super::*;
+    use rand::random;
 
     #[test]
-    fn smoke() { assert!(true) }
+    fn smoke() {
+        assert!(true)
+    }
 
     #[test]
     fn written_data_comes_back() {
@@ -58,8 +43,8 @@ mod test {
         // 100,000 random read/writes to ram that all read back right
         for _ in 0..100_000 {
             let mut offset: u16 = random();
-            println!("SIze = {SIZE_32KB}");
-            let value: u8 =random();
+            println!("Size = {SIZE_32KB}");
+            let value: u8 = random();
             println!("Wrote [{value:02x}] to [{offset:04x}]");
             ram.write(&offset, &value);
 

core/src/periph/hm62256/ramchip.rs

@@ -0,0 +1,12 @@
+use crate::constants::constants_system::SIZE_32KB;
+use crate::periph::hm62256::Hm62256;
+use crate::periph::ram_chip::RamChip;
+
+impl RamChip for Hm62256 {
+    fn write(&mut self, offset: &u16, value: &u8) {
+        let effective = *offset as i32 % SIZE_32KB as i32;
+        println!("Writing at E[{effective:04x}] / O[{offset:04x}]");
+        self.data[effective as usize] = *value;
+    }
+}
+

core/src/periph/hm62256/romchip.rs

@@ -0,0 +1,19 @@
+use log::debug;
+use crate::constants::constants_system::SIZE_32KB;
+use crate::periph::hm62256::Hm62256;
+use crate::periph::rom_chip::RomChip;
+
+impl RomChip for Hm62256 {
+
+
+    fn read(&self, offset: &u16) -> u8 {
+        // loops memory around past 32k
+        let effective = *offset as i32 % SIZE_32KB as i32;
+        self.data[effective as usize]
+    }
+
+    fn program(_: &[u8; SIZE_32KB]) -> Box<Self> {
+        debug!("Dont program ram.");
+        Hm62256::default().into()
+    }
+}

core/src/periph/hm62256/tick.rs

@@ -0,0 +1,33 @@
+use crate::periph::hm62256::Hm62256;
+
+impl Hm62256 {
+    fn tick(&mut self, address_bus: u16, data_bus: u8, read_mode: bool) -> (u16, u8) {
+        let new_data_bus = if read_mode {
+            // reading from ram
+            self.data[address_bus as usize]
+        } else {
+            // writing to ram
+            self.data[address_bus as usize] = data_bus.into();
+            data_bus
+        };
+        (address_bus, new_data_bus)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn smoke() { assert!(true); }
+
+    #[test]
+    fn write_to_memory_read_back_works_at_0() {
+        let mut ram = Hm62256::default();
+
+        ram.tick(0x0000, 0xab, false);
+        let (_, new_data) = ram.tick(0x0000, 0x00, true);
+
+        assert_eq!(new_data, 0xab);
+    }
+}

core/src/periph/mod.rs

@@ -1,6 +1,5 @@
 pub mod rom_chip;
 
 pub mod at28c256;
-pub mod ram_chip;
 pub mod hm62256;
-
+pub mod ram_chip;

core/tests/execution_tests.rs

@@ -0,0 +1 @@
+

core/tests/instruction_encode_decode.rs

@@ -0,0 +1 @@
+

macroquad/Cargo.toml

@@ -4,4 +4,5 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-macroquad.workspace = true
+macroquad.workspace = true
+core = {  path = "../core" }

macroquad/src/bin/rom_only.rs

@@ -0,0 +1,31 @@
+use macroquad::prelude::*;
+use core::computers::rom_only::backplane::Backplane;
+pub struct UiState {
+    display_offset: u16,
+    current_offset: u16
+}
+
+#[macroquad::main("Rom_Only")]
+async fn main() {
+    
+    let mut backplane =  Backplane::new();
+    let mut state = UiState { display_offset: 0x00, current_offset: 0x00 };
+    
+    loop {
+        clear_background(BLUE);
+        
+        draw_text("ROM ONLY", 20.0, 20.0, 30.0, DARKGRAY);
+        
+        backplane.tick();
+
+        draw_text(
+            format!("Display Offset: 0x{:04x}", state.display_offset).as_str(), 20.0, 60.0, 30.0, DARKGRAY
+        );
+
+        draw_text(
+            format!("Current Offset: 0x{:04x}", state.current_offset).as_str(), 20.0, 100.0, 30.0, DARKGRAY
+        );
+
+        next_frame().await
+    }
+}