Add ability to load from i/o registers relative to immediate

jsmoo
Nick Krichevsky 2022-04-08 21:10:47 -04:00
parent 75235ad5e0
commit e2365aec7e
3 changed files with 97 additions and 0 deletions

View File

@ -107,6 +107,16 @@ impl Processor {
self.registers.set_combined_register(dst, dst_address + 1);
}
Instruction::LDToMemoryRelativeToIORegisterStartByImmediate { src, offset } => {
let dst_address = memory::IO_REGISTER_START_ADDRESS + usize::from(offset);
let load_res = self.load_from_register_to_address(dst_address, src);
assert_ok!(load_res);
}
Instruction::LDFromMemoryRelativeToIORegisterStartByImmediate { dst, offset } => {
let src_address = memory::IO_REGISTER_START_ADDRESS + usize::from(offset);
let load_res = self.load_from_address_to_register(dst, src_address);
assert_ok!(load_res);
}
}
self.num_cycles += u64::from(instruction.cycles);
@ -464,4 +474,34 @@ mod tests {
.get_combined_register(register::Combined::HL)
);
}
#[test]
fn test_load_to_io_register_zone_by_immediate() {
let mut processor = Processor::default();
processor.registers.a = 0xAF;
let data = [0xE0, 0x05, 0x06];
let (ins, extra_data) =
RunnableInstruction::from_data(&data).expect("could not parse instruction");
assert_eq!(extra_data, &[0x06]);
processor.run(&ins);
assert_eq!(Some(0xAF), processor.memory.get(0xFF05));
}
#[test]
fn test_load_from_io_register_zone_by_immediate() {
let mut processor = Processor::default();
processor.memory.set(0xFF05, 0xAF);
let data = [0xF0, 0x05, 0x06];
let (ins, extra_data) =
RunnableInstruction::from_data(&data).expect("could not parse instruction");
assert_eq!(extra_data, &[0x06]);
processor.run(&ins);
assert_eq!(0xAF, processor.registers.a);
}
}

View File

@ -34,6 +34,16 @@ pub enum Instruction {
// A register whose value will be used to get the address relative to FF00
offset_register: register::Single,
},
// 3.3.1.20
LDFromMemoryRelativeToIORegisterStartByImmediate {
dst: register::Single,
offset: u8,
},
// 3.3.1.19
LDToMemoryRelativeToIORegisterStartByImmediate {
offset: u8,
src: register::Single,
},
LDFromImmediateAddress {
src_address: u16,
dst: register::Single,

View File

@ -68,6 +68,13 @@ fn parse_load_from_address_to_register(data: &[u8]) -> ParseResult {
register::Single::A,
data,
),
0xF0 => make_ld_from_memory_relative_to_io_register_start_by_immediate(
register::Single::A,
data,
),
0xE0 => {
make_ld_to_memory_relative_to_io_register_start_by_immediate(register::Single::A, data)
}
_ => Err(Error::UnknownOpcode(opcode)),
}
@ -227,6 +234,46 @@ fn make_ld_to_memory_relative_to_io_register_start(
.ok_or(Error::NoData)
}
fn make_ld_to_memory_relative_to_io_register_start_by_immediate(
src: register::Single,
data: &[u8],
) -> ParseResult {
let opcode = parse::get_opcode_from_data(data)?;
let value = data.get(1).ok_or(Error::NotEnoughArgs(opcode))?;
Ok((
RunnableInstruction {
instruction: Instruction::LDToMemoryRelativeToIORegisterStartByImmediate {
src,
offset: *value,
},
// guaranteed to succeed given we got the value
cycles: 12,
},
&data[2..],
))
}
fn make_ld_from_memory_relative_to_io_register_start_by_immediate(
dst: register::Single,
data: &[u8],
) -> ParseResult {
let opcode = parse::get_opcode_from_data(data)?;
let value = data.get(1).ok_or(Error::NotEnoughArgs(opcode))?;
Ok((
RunnableInstruction {
instruction: Instruction::LDFromMemoryRelativeToIORegisterStartByImmediate {
offset: *value,
dst,
},
cycles: 12,
},
// guaranteed to succeed given we got the value
&data[2..],
))
}
fn make_ld_to_address_then_do_arithmetic<
F: Fn(register::Combined, register::Single) -> Instruction,
>(