Crate intel8080[−][src]
Expand description
Yet another Intel 8080 Emulator. It passes the TST8080, 8080PRE, CPUTEST and 8080EXM tests.
Example for a small loop:
use intel8080::CPU;
let mut c = CPU::new();
c.pc = 0x0100; // sets pc to $100
// Here we create a small machine code program for demo purpose.
// Usually you will rather load an assembled code in memory (see below).
c.bus.write_byte(0x0100, 0x3e); // MVI A,$0F
c.bus.write_byte(0x0101, 0x0F);
c.bus.write_byte(0x0102, 0x3d); // DCR A
c.bus.write_byte(0x0103, 0xc2); // JNZ $0102
c.bus.write_word(0x0104, 0x0102);
c.bus.write_byte(0x0106, 0xc9); // RET
loop {
c.execute();
if c.pc == 0x0000 { break }
}
You can load assembled programs from disk to memory:
c.pc = 0x0100; // sets pc to $100
c.bus.load_bin("bin/loop.bin", 0x100).unwrap(); // loads file at address $100
loop {
c.execute();
if c.pc == 0x0000 { break }
}
It’s easy to create an interrupt request:
c.bus.load_bin("bin/interrupt.bin", 0).unwrap();
c.int = (true, 0xcf); // we create an interrupt request : flag set to true
loop { // and its associated RST command
c.execute(); // test program is designed to never leave a loop
if c.pc == 0x0000 { break } // if it does not execute the interrupt routine
}
Starting with 0.8.0, a more stabilized I/O system:
c.bus.write_byte(0x0000, 0x3e); // MVI A,$55
c.bus.write_byte(0x0001, 0x55);
c.bus.write_byte(0x0002, 0xd3); // OUT 1
c.bus.write_byte(0x0003, 0x01);
loop {
c.execute();
// Data sent from CPU to device 1 (OUT) ? let's handle it
if let Some(v) = c.bus.get_io_out(1) {
assert_eq!(v, 0x55);
// OUT handled ? let's clear it
c.bus.clear_io_out();
}
if c.pc == 0x0004 { break }
}
Starting with 0.13.0, a field has been added to define a read-only area in the address space:
use intel8080::{CPU, memory::ROMSpace};
let mut c = CPU::new();
c.bus.rom_space = Some(ROMSpace{start: 0xfff0, end: 0xffff});
Debug mode outputs CPU state and disassembled code to an internal string after each execute():
3E 0f MVI A,$0f
PC : 0x0003 SP : 0xff00 S : 0 Z : 0 A : 0 P : 0 C : 0
B : 0x00 C : 0x00 D : 0x00 E : 0x00 H : 0x00 L : 0x00 ...
Includes a “cpmloader” which loads and executes basic CP/M programs:
cargo run --release --example cpmloader -- bin/helloworld.bin
You can also check my Altair 8800 / 88-SIO / teletype emulator.
The provided source code examples can be assembled with Retro Assembler.