more instructions and tests passing.

core/src/periph/at28c256/default.rs

@@ -0,0 +1,22 @@
+use crate::constants::constants_system::SIZE_32KB;
+use crate::periph::at28c256::At28C256;
+use crate::periph::hm62256::Hm62256;
+
+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,
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn smoke() { assert!(true); }
+}

core/src/periph/at28c256/mod.rs

@@ -0,0 +1,39 @@
+mod default;
+mod rom_chip;
+
+use crate::constants::constants_system::SIZE_32KB;
+use crate::periph::rom_chip::RomChip;
+
+/// At28C256
+///
+/// Represents a single At28C256 Chip
+///
+/// 256kbit storage
+/// 32kbyte storage
+pub struct At28C256 {
+    data: Box<[u8; SIZE_32KB]>,
+}
+
+#[cfg(test)]
+mod test {
+    use crate::constants::constants_system::SIZE_1KB;
+    use super::*;
+
+    #[test]
+    fn smoke() {
+        assert!(true)
+    }
+
+    #[test]
+    fn programmed_data_reads_back_same() {
+        let mut data = At28C256::default();
+        for i in 0..SIZE_32KB {
+            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)));
+        }
+    }
+}

core/src/periph/at28c256/rom_chip.rs

@@ -0,0 +1,27 @@
+use crate::constants::constants_system::SIZE_32KB;
+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]
+    }
+
+    fn program(new_data: Box<[u8; SIZE_32KB]>) -> Box<At28C256> {
+        println!("Writing new chip.");
+        let mut working = At28C256::default();
+        working.data = Box::new(*new_data);
+        working.into()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn smoke() { assert!(true); }
+
+
+}