picsim

PIC12F508 Simulator in rust

cargo run --example from_hex_file

Implements an 8-bit PIC12F508 microcontroller. Programs can be loaded from hex-files (compiled by the mplab pic-as.exe compiler) or written directly as opcodes in rust. Instructions in the 12F508 are 12 bits wide. These can be encoded and decoded by the OpCode enum associated functions.

Implemented:

• All instructions of the pic baseline instruction set (33 instructions)
• Instruction encoding (to 12-bit words) and decoding (to structs in rust)
• Program branches and regular linear execution
• Branches 2-cycle delay
• 2 levels deep call stack for CALL and RETLW instructions
• GPIO input and output
• TMR0 with prescale, and 2-cycle delay after TMR0 reg write
• Indirect adressing via INDF and FSR registers
• STATUS bits affected by arithmetic operations
• WD timer with timeouts
• SLEEP and wake from sleep
• MCLR reset

Not implemented:

• TMR0 in counter mode
• config word settings

Fun TODOs

• Small assembly compiler
• GUI