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register.go
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register.go
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package cpu6502
func lda(cpu *CPU, am AddressMode) {
cpu.A = am.Read(cpu)
cpu.flagsNZ(cpu.A)
}
func ldx(cpu *CPU, am AddressMode) {
cpu.X = am.Read(cpu)
cpu.flagsNZ(cpu.X)
}
func ldy(cpu *CPU, am AddressMode) {
cpu.Y = am.Read(cpu)
cpu.flagsNZ(cpu.Y)
}
func sta(cpu *CPU, am AddressMode) {
am.WriteFast(cpu, cpu.A)
}
func stx(cpu *CPU, am AddressMode) {
am.WriteFast(cpu, cpu.X)
}
func sty(cpu *CPU, am AddressMode) {
am.WriteFast(cpu, cpu.Y)
}
func tax(cpu *CPU, am AddressMode) {
cpu.X = cpu.A
cpu.flagsNZ(cpu.X)
}
func txa(cpu *CPU, am AddressMode) {
cpu.A = cpu.X
cpu.flagsNZ(cpu.A)
}
func tay(cpu *CPU, am AddressMode) {
cpu.Y = cpu.A
cpu.flagsNZ(cpu.Y)
}
func tya(cpu *CPU, am AddressMode) {
cpu.A = cpu.Y
cpu.flagsNZ(cpu.A)
}
func dex(cpu *CPU, am AddressMode) {
// X - 1 -> X
am.Implied(cpu)
cpu.X -= 1
cpu.flagsNZ(cpu.X)
}
func inx(cpu *CPU, am AddressMode) {
am.Implied(cpu)
cpu.X += 1
cpu.flagsNZ(cpu.X)
}
func dey(cpu *CPU, am AddressMode) {
// Y - 1 -> Y
am.Implied(cpu)
cpu.Y -= 1
cpu.flagsNZ(cpu.Y)
}
func iny(cpu *CPU, am AddressMode) {
am.Implied(cpu)
cpu.Y += 1
cpu.flagsNZ(cpu.Y)
}
func lax(cpu *CPU, am AddressMode) {
v := am.Read(cpu)
cpu.A = v
cpu.X = v
cpu.flagsNZ(v)
}
func sax(cpu *CPU, am AddressMode) {
// A AND X -> M
// no flags
v := cpu.A & cpu.X
am.Write(cpu, v)
}