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Fixed ADC and SBC non BCD. Passing tests up to 41

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This commit is contained in:
Ivan Izaguirre 2019-02-10 17:49:11 +01:00
parent 6e524093c1
commit f43150c93c
2 changed files with 27 additions and 11 deletions
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28
execute.go
View File

@ -191,6 +191,7 @@ func buildOpBranch(flag uint8, value bool) opFunc {
func opBIT(s *state, line []uint8, opcode opcode) {
value, _, _ := resolve(s, line, opcode)
acc := s.registers.getA()
// Future note: The immediate addressing mode (65C02 or 65816 only) does not affect V.
s.registers.updateFlag(flagZ, value&acc == 0)
s.registers.updateFlag(flagN, value&(1<<7) != 0)
s.registers.updateFlag(flagV, value&(1<<6) != 0)
@ -227,11 +228,15 @@ func opADC(s *state, line []uint8, opcode opcode) {
total := uint16(s.registers.getA()) +
uint16(value) +
uint16(s.registers.getFlagBit(flagC))
signedTotal := int16(int8(s.registers.getA())) +
int16(int8(value)) +
int16(s.registers.getFlagBit(flagC))
truncated := uint8(total)
s.registers.setA(truncated)
s.registers.updateFlagZN(truncated)
s.registers.updateFlag(flagC, total > 0xFF)
// TODO: missing overflow flag
s.registers.updateFlag(flagV, signedTotal < -128 || signedTotal > 127)
}
}
@ -242,13 +247,16 @@ func opSBC(s *state, line []uint8, opcode opcode) {
panic("BCD not supported")
} else {
total := 0x100 + uint16(s.registers.getA()) -
uint16(value) -
uint16(s.registers.getFlagBit(flagC))
uint16(value) +
uint16(s.registers.getFlagBit(flagC)) - 1
signedTotal := int16(int8(s.registers.getA())) -
int16(int8(value)) +
int16(s.registers.getFlagBit(flagC)) - 1
truncated := uint8(total)
s.registers.setA(truncated)
s.registers.updateFlagZN(truncated)
s.registers.updateFlag(flagC, total <= 0xFF)
// TODO: missing overflow flag
s.registers.updateFlag(flagC, total > 0xFF)
s.registers.updateFlag(flagV, signedTotal < -128 || signedTotal > 127)
}
}
@ -505,15 +513,19 @@ func executeLine(s *state, line []uint8) {
opcode.action(s, line, opcode)
}
func executeInstruction(s *state) {
func executeInstruction(s *state, log bool) {
pc := s.registers.getPC()
opcode := opcodes[s.memory[pc]]
pcNext := pc + uint16(opcode.bytes)
s.registers.setPC(pcNext)
line := s.memory[pc:pcNext]
fmt.Printf("%#04x %-10s: ", pc, lineString(s, line, opcode))
if log {
fmt.Printf("%#04x %-12s: ", pc, lineString(s, line, opcode))
}
opcode.action(s, line, opcode)
fmt.Printf("%v, %x\n", s.registers, line)
if log {
fmt.Printf("%v, %x\n", s.registers, line)
}
}
func lineString(s *state, line []uint8, opcode opcode) string {

10
main.go
View File

@ -10,11 +10,15 @@ func main() {
for true {
for i := 0; i < 20; i++ {
testCase := s.memory[0x0200]
fmt.Printf("[ %d ] ", testCase)
log := testCase > 41
if log {
fmt.Printf("[ %d ] ", testCase)
}
pc := s.registers.getPC()
executeInstruction(&s)
executeInstruction(&s, log)
if pc == s.registers.getPC() {
s.memory.printPage(0x01)
s.memory.printPage(0x00)
//s.memory.printPage(0x01)
panic("No change in PC")
}
}