starting to work on loading programs to the system

Cargo.lock

@@ -72,7 +72,7 @@ version = "0.1.0"
 dependencies = [
  "ceres-asm 0.1.0",
  "ceres-sys 0.1.0",
- "offbrand 0.1.0",
+ "offbrand 0.1.0 (git+https://github.com/izzabelle/offbrand)",
  "structopt 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "thiserror 1.0.20 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -88,6 +88,9 @@ dependencies = [
 [[package]]
 name = "ceres-sys"
 version = "0.1.0"
+dependencies = [
+ "thiserror 1.0.20 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "cfg-if"
@@ -427,6 +430,7 @@ dependencies = [
 [[package]]
 name = "offbrand"
 version = "0.1.0"
+source = "git+https://github.com/izzabelle/offbrand#e4ec4d2a8081595d6412acd60c2448d37a1614f4"
 dependencies = [
  "image 0.23.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "minifb 0.16.0 (git+https://github.com/emoon/rust_minifb)",
@@ -1065,6 +1069,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum num-rational 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "5c000134b5dbf44adc5cb772486d335293351644b801551abe8f75c84cfa4aef"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
 "checksum num_cpus 1.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "05499f3756671c15885fee9034446956fff3f243d6077b91e5767df161f766b3"
+"checksum offbrand 0.1.0 (git+https://github.com/izzabelle/offbrand)" = "<none>"
 "checksum once_cell 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0b631f7e854af39a1739f401cf34a8a013dfe09eac4fa4dba91e9768bd28168d"
 "checksum orbclient 0.3.27 (registry+https://github.com/rust-lang/crates.io-index)" = "f8b18f57ab94fbd058e30aa57f712ec423c0bb7403f8493a6c58eef0c36d9402"
 "checksum pkg-config 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)" = "05da548ad6865900e60eaba7f589cc0783590a92e940c26953ff81ddbab2d677"

Cargo.toml

@@ -5,8 +5,8 @@ authors = ["Izzy <me@izzabelle.dev>"]
 edition = "2018"
 
 [dependencies]
-#offbrand = { git = "https://github.com/izzabelle/offbrand" }
-offbrand = { path = "../offbrand" }
+offbrand = { git = "https://github.com/izzabelle/offbrand" }
+#offbrand = { path = "../offbrand" }
 structopt = "0.3.14"
 ceres-sys = { path = "ceres-sys" }
 ceres-asm = { path = "ceres-asm" }

ceres-asm/Cargo.toml

@@ -4,8 +4,6 @@ version = "0.1.0"
 authors = ["Isabelle L. <me@izzabelle.dev>"]
 edition = "2018"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
 logos = "0.11.4"
 thiserror = "1.0.20"

ceres-sys/Cargo.toml

@@ -4,6 +4,5 @@ version = "0.1.0"
 authors = ["Isabelle L. <me@izzabelle.dev>"]
 edition = "2018"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
+thiserror = "1.0.20"

ceres-sys/src/lib.rs

@@ -13,6 +13,16 @@ pub const SCREEN_HEIGHT: usize = 144;
 /// ceres video memory buffer length
 pub const VIDEO_MEMORY_LEN: usize = SCREEN_HEIGHT * SCREEN_WIDTH;
 
+/// result type
+pub type Result<T> = std::result::Result<T, CeresSystemError>;
+
+/// error type
+#[derive(Debug, thiserror::Error)]
+pub enum CeresSystemError {
+    #[error(transparent)]
+    StdIo(#[from] std::io::Error),
+}
+
 /// the core system structure of ceres
 pub struct System {
     pub registers: Registers,

ceres-sys/src/memory.rs

@@ -1,3 +1,6 @@
+use crate::Result;
+use std::{io::Read, path::PathBuf};
+
 /// all the memory as one big fat fucking slice
 pub struct Memory {
     data: [u16; std::u16::MAX as usize],
@@ -8,6 +11,21 @@ impl Memory {
     pub fn init() -> Memory {
         Memory { data: [0x00; std::u16::MAX as usize] }
     }
+
+    /// loads a program to the memory
+    pub fn load_program(&mut self, path: PathBuf) -> Result<()> {
+        // load bytes
+        let mut file = std::fs::File::open(path)?;
+        let mut raw_data: Vec<u8> = Vec::new();
+        file.read(&mut raw_data)?;
+
+        // construct words
+        (0..(raw_data.len() / 2)).for_each(|i| {
+            let bytes: [u8; 2] = [raw_data[i * 2], raw_data[i * 2 + 1]];
+            self.data[i] = u16::from_le_bytes(bytes);
+        });
+        Ok(())
+    }
 }
 
 impl std::ops::Index<u16> for Memory {