adjustable memory size

src/emulator/main.rs

@@ -3,6 +3,8 @@ use instructions::arithmetic;
 
 mod instructions;
 
+const MEMORY_SIZE: usize = 8192;
+
 pub struct EmulatorState {
     a: u8,
     b: u8,
@@ -21,7 +23,7 @@ pub struct EmulatorState {
     /// Enable interrupts
     ei: bool,
     /// Memory map
-    memory: [u8; 8000],
+    memory: [u8; MEMORY_SIZE],
 }
 
 pub struct ConditionCodes {
@@ -117,7 +119,7 @@ fn main() {
         cc: ConditionCodes { z: true, s: true, p: true, c: true },
         pc: 0,
         ei: true,
-        memory: [0; 8000],
+        memory: [0; MEMORY_SIZE],
     };
 
     // Load the ROM into memory
@@ -127,13 +129,16 @@ fn main() {
         .expect("Provide a path to a ROM file to emulate as an argument");
     let file = fs::read(filename).expect("where file");
 
-    for i in 0..8000 {
+    for i in 0..8192 {
         state.memory[i] = file[i];
     }
 
-    while state.pc < 8000 {
+    while state.pc < 8192 {
         tick(&mut state);
     }
+
+    println!("Program counter reached end of memory; exiting");
+    print_state(&state);
 }
 
 fn tick(state: &mut EmulatorState) {