A Simple Z80 Machine

z80-test.go

package main

import (
	"fmt"
	"github.com/remogatto/z80"
)

type Memory struct {
	memory []byte
}

func NewMemory() *Memory {
	return &Memory{
		memory: []byte{
			0x21, 0x0C, 0x00, // ld hl, 0008
			0x06, 0x0F, // ld b,0f
			0x7e,       // ld a,(hl)
			0x23,       // inc hl
			0xD3, 0x00, // out (00), a
			0x10, 0xFA, // djnz
			0x76,                         // halt
			0x48, 0x65, 0x6C, 0x6C, 0x6F, // Message ASCII
			0x20, 0x77, 0x6F, 0x72, 0x6C, //
			0x64, 0x21, 0x20, 0x0D, 0x0A,
		},
	}
}

func (m *Memory) ReadByte(address uint16) byte {
	return m.ReadByteInternal(address)
}

func (m *Memory) ReadByteInternal(address uint16) byte {
	return m.memory[address]
}

func (m *Memory) WriteByte(address uint16, value byte) {
	m.WriteByteInternal(address, value)
}

func (m *Memory) WriteByteInternal(address uint16, value byte) {
	m.memory[address] = value
}

func (m *Memory) Read(address uint16) byte                                     { return 0 }
func (m *Memory) Write(address uint16, value byte, protectROM bool)            {}
func (m *Memory) ContendRead(address uint16, time int)                         {}
func (m *Memory) ContendReadNoMreq(address uint16, time int)                   {}
func (m *Memory) ContendReadNoMreq_loop(address uint16, time int, count uint)  {}
func (m *Memory) ContendWriteNoMreq(address uint16, time int)                  {}
func (m *Memory) ContendWriteNoMreq_loop(address uint16, time int, count uint) {}

func (m *Memory) Data() []byte {
	return m.memory
}

type Ports struct{}

func (p *Ports) ReadPort(address uint16) byte {
	return p.ReadPortInternal(address, true)
}

func (p *Ports) ReadPortInternal(address uint16, contend bool) byte {
	return 0
}

func (p *Ports) WritePort(address uint16, b byte) {
	p.WritePortInternal(address, b, true)
}

func (p *Ports) WritePortInternal(address uint16, b byte, contend bool) {
	fmt.Print(string(b))
}

func (p *Ports) ContendPortPreio(address uint16)  {}
func (p *Ports) ContendPortPostio(address uint16) {}

func NewPorts() *Ports {
	return &Ports{}
}

func main() {
	z80 := z80.NewZ80(NewMemory(), NewPorts())

	z80.Reset()

	for !z80.Halted {
		z80.DoOpcode()
	}
}