From 7656cf8b05f581ba440040ee4e211d911c0c7cac Mon Sep 17 00:00:00 2001
From: Isaac Marovitz <isaacryu@icloud.com>
Date: Thu, 14 Dec 2023 00:34:37 -0500
Subject: [PATCH] Boot!

---
 src/main.rs      | 9 +++++----
 src/mmu.rs       | 4 +++-
 src/ppu.rs       | 1 +
 src/registers.rs | 2 +-
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index a61d7c2..a12ef32 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -29,21 +29,22 @@ pub const STEP_CYCLES: u32 = (STEP_TIME as f64 / (1000_f64 / CLOCK_FREQUENCY as
 #[derive(Parser)]
 struct Args {
     rom_path: String,
+    boot_rom: String
 }
 
 #[tokio::main]
 async fn main() -> Result<(), impl std::error::Error> {
     let args = Args::parse();
     let mut file = File::open(args.rom_path).expect("No ROM found!");
+    let mut boot = File::open(args.boot_rom).expect("No Boot ROM found!");
     let mut buffer = Vec::new();
+    let mut boot_rom = Vec::new();
 
     file.read_to_end(&mut buffer).expect("Failed to read ROM!");
-
-    let nintendo_logo = &buffer[0x0104..=0x0133];
+    boot.read_to_end(&mut boot_rom).expect("Failed to read Boot ROM!");
 
     // Display Nintendo Logo
-
-    // Run checksum
+    buffer[0..=0x00FF].copy_from_slice(boot_rom.as_slice());
 
     // Get game name
     let name_data = &buffer[0x0134..=0x0143];
diff --git a/src/mmu.rs b/src/mmu.rs
index 03f94a4..930a9dc 100644
--- a/src/mmu.rs
+++ b/src/mmu.rs
@@ -74,7 +74,8 @@ impl MMU {
 
     pub fn write(&mut self, a: u16, v: u8) {
         match a {
-            0x0000..=0x7FFF => self.rom[a as usize] = v,
+            // TODO: MBC
+            0x0000..=0x7FFF => {}
             0x8000..=0x9FFF => self.ppu.write(a, v),
             // TODO: MBC
             0xA000..=0xBFFF => {}
@@ -94,6 +95,7 @@ impl MMU {
             // TODO: APU
             0xFF10..=0xFF3F => {},
             0xFF0F => self.intf = Interrupts::from_bits(v).unwrap(),
+            0xFF50 => {},
             0xFF70 => self.wram_bank = match v & 0x07 { 0 => 1, n => n as usize },
             0xFFFF => self.inte = Interrupts::from_bits_truncate(v),
             _ => panic!("Write to unsupported address ({:#06x})!", a),
diff --git a/src/ppu.rs b/src/ppu.rs
index d2942c8..065338d 100644
--- a/src/ppu.rs
+++ b/src/ppu.rs
@@ -434,6 +434,7 @@ impl PPU {
             0xFF49 => self.op1,
             0xFF4A => self.wy,
             0xFF4B => self.wx,
+            0xFF4D => 0x00,
             0xFF4F => 0xFE | self.ram_bank as u8,
             _ => panic!("Read to unsupported PPU address ({:#06x})!", a),
         }
diff --git a/src/registers.rs b/src/registers.rs
index d2a0405..1f128ab 100644
--- a/src/registers.rs
+++ b/src/registers.rs
@@ -93,7 +93,7 @@ impl Registers {
                     e: 0xD8,
                     h: 0x01,
                     l: 0x4D,
-                    pc: 0x0100,
+                    pc: 0x0000,
                     sp: 0xFFFE
                 }
             },