Gemma now has a test that runs the IBM Logo and verifies the video is as expected when done.

gemma/src/chip8/instructions.rs

@@ -1190,7 +1190,7 @@ mod test {
         x.registers.poke(0x1, 0x10);
         x.registers.poke(0x2, 0x08);
         Chip8CpuInstructions::SubVxVy(0x1, 0x02).execute(&mut x);
-        assert_eq!(x.registers.peek(0xf), 0);
+        assert_eq!(x.registers.peek(0xf), 1);
         assert_eq!(x.registers.peek(0x1), 0x8);
         assert_eq!(x.registers.peek_pc(), 0x202);
     }
@@ -1249,7 +1249,7 @@ mod test {
         // expect the result to be 0x0b
         assert_eq!(x.registers.peek(0x1), 0x0b);
         // expect the vf register to be set to 1 as there was overflow
-        assert_eq!(x.registers.peek(0xf), 0x0);
+        assert_eq!(x.registers.peek(0xf), 0x1);
 
         let mut x = Chip8Computer::new();
         x.registers.poke(0x01, 0xab);
@@ -1258,7 +1258,7 @@ mod test {
 
         // expect the result to be 11110101, -0xB, -11, 245, 0xF5
         assert_eq!(x.registers.peek(0x1), 0xf5);
-        assert_eq!(x.registers.peek(0xf), 0x1);
+        assert_eq!(x.registers.peek(0xf), 0x0);
     }
 
     #[test]