From 1a93e04fe50d59f0c524e8f4dd53d48a287adfde Mon Sep 17 00:00:00 2001
From: Jacob McDonnell <jacob@jacobmcdonnell.com>
Date: Sun, 5 May 2024 02:13:51 -0400
Subject: Initial Commit

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+# QDME - Quick and Dirty MIPS Emulator
+
+## Intro
+
+QDME is a simple MIPS emulator written in C. Currently the binary file must be
+manually created, eventually this will change.
+
+## Instructions
+|Instruction|Type|Action|
+|-----------|----|------|
+|add        |R   |rd = rs + rt|
+|addu       |R   |rd = rs + rt|
+|and        |R   |rd = rs & rt|
+|or         |R   |rd = rs \| rt|
+|slt        |R   |rd = rs < rt|
+|sltu       |R   |rd = rs < rt|
+|sub        |R   |rd = rs - rt|
+|subu       |R   |rd = rs - rt|
+|xor        |R   |rd = rs ^ rt|
+|sll        |R   |rd = rt << shamt|
+|sra        |R   |rd = rt >> shamt|
+|srl        |R   |rd = rt >> shamt|
+|div        |R   |hi = rs % rt lo = rs / rt|
+|divu       |R   |hi = rs % rt lo = rs / rt|
+|mult       |R   |hi, lo = rs * rt|
+|multu      |R   |hi, lo = rs * rt|
+|MFHI       |R   |rd = hi|
+|MFLO       |R   |rd = lo|
+|MTHI       |R   |rs = hi|
+|MTLO       |R   |rs = lo|
+|jr         |R   |pc = addr, pc = $ra|
+|jalr       |R   |rd = pc, pc = addr|
+|syscall    |R   |System Call|
+|jal        |J   |$ra = pc, pc = addr|
+|j          |J   |pc = addr|
+|beq        |I   | pc = (rs == rt) ? imm + pc + 4 : pc|
+|bne        |I   | pc = (rs != rt) ? imm + pc + 4 : pc|
+|addi       |I   |rt = rs + imm|
+|addiu      |I   |rt = rs + imm|
+|andi       |I   |rt = rs & imm|
+|ori        |I   |rt = rs \| imm|
+|xori       |I   |rt = rs ^ imm|
+|slti       |R   |rt = rs < imm|
+|sltiu      |R   |rt = rs < imm|
+|lui        |I   |rt = rs << 16|
+|lw         |I   |rs = imm(rt)|
+|sw         |I   |imm(rt) = rs|
+
+## Syscalls
+
+|Syscall|Action|
+|-------|------|
+|1      |Print integer in $a0|
+|2      |Not Implemented Yet|
+|3      |Not Implemented Yet|
+|4      |Print Null Terminated String, address in $a0|
+|5      |Read integer into $v0|
+|6      |Not Implemented Yet|
+|7      |Not Implemented Yet|
+|8      |Read string of length $a0 into memory at $a1|
+|9      |Not Implemented Yet|
+|10     |Exit with Status code 0|
+|11     |Print Character in $a0|
+|12     |Read Character into $v0|
+|13     |Not Implemented Yet|
+|14     |Not Implemented Yet|
+|15     |Not Implemented Yet|
+|16     |Not Implemented Yet|
+|17     |Exit with Status Code in $0|
+
-- 
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