From 60732c4d90abe71d990ca00894f41b5078857a60 Mon Sep 17 00:00:00 2001
From: WlodekM <wlodzio.maly@gmail.com>
Date: Thu, 3 Apr 2025 11:51:48 +0300
Subject: readme

---
 README.md  | 26 +++++++++++++++++++++++++-
 runtime.ts | 18 +++++++++++++-----
 2 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index ec5beeb..5a6ff4c 100644
--- a/README.md
+++ b/README.md
@@ -4,4 +4,28 @@ a 65c02 emulator written in typescript
 
 do NOT use this
 
-i am the worst typescript developer ever and it's a miracle that this thing works
\ No newline at end of file
+i am the worst typescript developer ever and it's a miracle that this thing works
+
+if you do want to use it, here's how you can use the built-in runtime
+
+```bash
+deno -A runtime.ts <binary>
+```
+
+options:
+ - `-d` - debug
+ - `-b`/`--binstart` - start of binary
+
+debug mode:
+in debug mode, on each cycle, the runtime logs every instructions and pauses for input
+
+the input can either be any of the following commands or anything else, if the input isn't a command the runtime continues execution to the next instruction
+
+commands:
+ - `b` - break, exit
+ - `i` - inspect
+ - `s` - inspect stack
+ - `k[NUM]` - skip
+ - `r[ADR]` - breakpoint
+ - `g[ADR]` - goto, change PC
+ - `I[INS]` - breakpoint instruction
\ No newline at end of file
diff --git a/runtime.ts b/runtime.ts
index d400031..2e6723f 100644
--- a/runtime.ts
+++ b/runtime.ts
@@ -1,5 +1,6 @@
 import The65c02, { BitField, Pin } from "./65c02.ts";
 import matrix from "./opcode_matrix.json" with { type: "json" };
+import { parseArgs } from "jsr:@std/cli/parse-args";
 
 // the thing used for ram
 const ram = new Uint8Array(2**16);
@@ -16,17 +17,24 @@ const cpu = new The65c02(function (this: The65c02) {
 
 await cpu.loadInstructions()
 
+const args = parseArgs(Deno.args)
+
+const binStart = parseInt(args.b ?? args.binStart ?? '8000', 16)
+
+if (Number.isNaN(binStart))
+    throw 'binStart is NaN!'
+
 // mem address $0000
-ram[0xFFFC] = 0x00
-ram[0xFFFD] = 0x00
+ram[0xFFFC] = binStart & 0x00FF
+ram[0xFFFD] = binStart & 0xFF00
 
 // read code from file
-const code = Deno.readFileSync('a.out')
+const code = Deno.readFileSync(args._.toString() || 'msbasic/tmp/eater.bin')
 
 // write code to ram before execution
 for (let offset = 0; offset < code.length; offset++) {
     const byte = code[offset];
-    ram[0x0000 + offset] = byte;
+    ram[binStart  + offset] = byte;
 }
 
 // pull RESB low to reset the 65c02
@@ -102,7 +110,7 @@ while (!cpu.io.interruptRequest.high) {
         } else if (i[0] == 's'.charCodeAt(0)) {
             console.log('stack:')
             for (let i = 0; i < cpu.stackPointer.num(); i++) {
-                console.log(` ${i.toString(16).padStart(2, '0')} ${ram[0x01FF - i].toString(2).padStart(8, '0')} (0x${ram[0x01FF - i].toString(16).padStart(4, '0')} ${ram[0x01FF - i]})`)
+                console.log(` ${i.toString(16).padStart(2, '0')} ${ram[0x01FF - i].toString(2).padStart(8, '0')} (0x${ram[0x01FF - i].toString(16).padStart(4, '0')} ${ram[0x01FF - i].toString().padStart(3)})`)
             }
         } else if (i[0] == 'k'.charCodeAt(0)) {
             const num = +(new TextDecoder().decode(i.slice(1, 7)).replaceAll('\0', ''));
-- 
cgit 1.4.1-2-gfad0