Merge branch 'master' into master

Cargo.toml

@@ -32,16 +32,19 @@ description = "A MOS 6502 Emulator"
 license = "BSD-3-Clause"
 version = "0.0.1"
 authors = ["The 6502-rs Developers"]
+build = "build.rs"
 
 [lib]
 # This will look in src/lib.rs
 name = "mos6502"
 
-[[bin]]
-# This will look in src/bin/mos6502.rs
-name = "mos6502"
-
 [dependencies]
 bitflags = "0.9.1"
 log = "0.3.8"
 num = "0.1"
+
+[build-dependencies]
+skeptic = "0.13"
+
+[dev-dependencies]
+skeptic = "0.13"

README.md

@@ -7,3 +7,113 @@ This started off as a fork of [6502-rs](https://github.com/amw-zero/6502-rs),
 which seems to be unmaintained at this point.
 
 It builds with the latest stable Rust.
+
+## Usage example
+
+```rust
+extern crate mos6502;
+
+use mos6502::cpu;
+use mos6502::address::Address;
+
+fn main() {
+    let mut cpu = cpu::CPU::new();
+
+    let zero_page_data = [
+        // ZeroPage data start
+        0x00,
+        0x02, // ADC ZeroPage target
+        0x00,
+        0x04, // ADC ZeroPageX target
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x10, // ADC IndexedIndirectX address
+        0x80, // ADC IndexedIndirectX address
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x08, // ADC IndirectIndexedY address
+        0x80, // ADC IndirectIndexedY address
+    ];
+
+    let program = [
+        // Code start
+        0xA9, // LDA Immediate
+        0x01, //     Immediate operand
+        0x69, // ADC Immediate
+        0x07, //     Immediate operand
+        0x65, // ADC ZeroPage
+        0x01, //     ZeroPage operand
+        0xA2, // LDX Immediate
+        0x01, //     Immediate operand
+        0x75, // ADC ZeroPageX
+        0x02, //     ZeroPageX operand
+        0x6D, // ADC Absolute
+        0x01, //     Absolute operand
+        0x80, //     Absolute operand
+        0xA2, // LDX immediate
+        0x08, //     Immediate operand
+        0x7D, // ADC AbsoluteX
+        0x00, //     AbsoluteX operand
+        0x80, //     AbsoluteX operand
+        0xA0, // LDY immediate
+        0x04, //     Immediate operand
+        0x79, // ADC AbsoluteY
+        0x00, //     AbsoluteY operand
+        0x80, //     AbsoluteY operand
+        0xA2, // LDX immediate
+        0x05, //     Immediate operand
+        0x61, // ADC IndexedIndirectX
+        0x03, //     IndexedIndirectX operand
+        0xA0, // LDY immediate
+        0x10, //     Immediate operand
+        0x71, // ADC IndirectIndexedY
+        0x0F, //     IndirectIndexedY operand
+        0xEA, // NOP :)
+        0xFF, // Something invalid -- the end!
+    ];
+
+    let data: [u8; 25] = [
+        0x00,
+        0x09, // ADC Absolute target
+        0x00,
+        0x00,
+        0x40, // ADC AbsoluteY target
+        0x00,
+        0x00,
+        0x00,
+        0x11, // ADC AbsoluteX target
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x12, // ADC IndexedIndirectX target
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x06, // ADC IndirectIndexedY target
+    ];
+
+    // "Load" a program
+    cpu.memory.set_bytes(Address(0x0000), &zero_page_data);
+    cpu.memory.set_bytes(Address(0x4000), &program);
+    cpu.memory.set_bytes(Address(0x8000), &data);
+
+    cpu.registers.program_counter = Address(0x4000);
+
+    cpu.run();
+
+    println!("{:?}", cpu);
+}
+```

build.rs

@@ -0,0 +1,5 @@
+extern crate skeptic;
+
+fn main() {
+    skeptic::generate_doc_tests(&["README.md"]);
+}

src/bin/mos6502.rs

@@ -39,10 +39,8 @@ fn main() {
 
     // "Load" a program
 
-    // JAM: FIXME: What's the syntax for specifying the array element type,
-    //             but not the length? (For a fixed-size array)
 
-    let zero_page_data: [u8; 17] = [
+    let zero_page_data = [
         // ZeroPage data start
         0x00,
         0x02, // ADC ZeroPage target
@@ -63,7 +61,7 @@ fn main() {
         0x80, // ADC IndirectIndexedY address
     ];
 
-    let program: [u8; 33] = [
+    let program = [
         // Code start
         0xA9, // LDA Immediate
         0x01, //     Immediate operand
@@ -100,7 +98,7 @@ fn main() {
         0xFF, // Something invalid -- the end!
     ];
 
-    let data: [u8; 25] = [
+    let data = [
         0x00,
         0x09, // ADC Absolute target
         0x00,

src/cpu.rs

@@ -410,13 +410,10 @@ impl CPU {
     }
 
     pub fn run(&mut self) {
-        loop {
+        while let Some(decoded_instr) = self.fetch_next_and_decode() {
-            if let Some(decoded_instr) = self.fetch_next_and_decode() {
                 self.execute_instruction(decoded_instr);
-            } else {
-                break;
-            }
             } 
+        
     }
 
     fn set_flags_from_i8(status: &mut Status, value: i8) {

src/registers.rs

@@ -58,17 +58,17 @@ impl StatusArgs {
 
 bitflags! {
     pub struct Status: u8 {
-        const PS_NEGATIVE           = 0b10000000;
+        const PS_NEGATIVE           = 0b1000_0000;
-        const PS_OVERFLOW           = 0b01000000;
+        const PS_OVERFLOW           = 0b0100_0000;
-        const PS_UNUSED             = 0b00100000; // JAM: Should this exist?
+        const PS_UNUSED             = 0b0010_0000; // JAM: Should this exist?
                                                   // (note that it affects the
                                                   // behavior of things like
                                                   // from_bits_truncate)
-        const PS_BRK                = 0b00010000;
+        const PS_BRK                = 0b0001_0000;
-        const PS_DECIMAL_MODE       = 0b00001000;
+        const PS_DECIMAL_MODE       = 0b0000_1000;
-        const PS_DISABLE_INTERRUPTS = 0b00000100;
+        const PS_DISABLE_INTERRUPTS = 0b0000_0100;
-        const PS_ZERO               = 0b00000010;
+        const PS_ZERO               = 0b0000_0010;
-        const PS_CARRY              = 0b00000001;
+        const PS_CARRY              = 0b0000_0001;
     }
 }
 

tests/skeptic.rs

@@ -0,0 +1 @@
+include!(concat!(env!("OUT_DIR"), "/skeptic-tests.rs"));