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monitor assembler address now supports '*' and relative addresses to that

This commit is contained in:
Irmen de Jong 2020-02-16 16:27:52 +01:00
parent 3f86d5185e
commit 606a587bb5
1 changed files with 15 additions and 3 deletions
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18
src/main/kotlin/razorvine/ksim65/Monitor.kt
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@ -123,7 +123,7 @@ class Monitor(val bus: Bus, val cpu: Cpu6502) {
// immediate
val instruction = instructions[Pair(mnemonic, Cpu6502.AddrMode.Imm)] ?: return IVirtualMachine.MonitorCmdResult("?invalid instruction", command, false)
bus.write(address, instruction.toShort())
bus.write(address+1, parseNumber(arg.substring(1), true).toShort())
bus.write(address+1, parseNumber(arg.substring(1), decimalFirst = true).toShort())
}
arg.startsWith("(") && arg.endsWith(",x)") -> {
// indirect X
@ -204,7 +204,7 @@ class Monitor(val bus: Bus, val cpu: Cpu6502) {
if (instr != null) {
// relative address
val rel = try {
parseNumber(arg)
parseRelativeToPC(arg, address)
} catch (x: NumberFormatException) {
return IVirtualMachine.MonitorCmdResult("?invalid instruction", command, false)
}
@ -213,7 +213,7 @@ class Monitor(val bus: Bus, val cpu: Cpu6502) {
} else {
// absolute or absZp
val absAddress = try {
parseNumber(arg)
parseRelativeToPC(arg, address)
} catch (x: NumberFormatException) {
return IVirtualMachine.MonitorCmdResult("?invalid instruction", command, false)
}
@ -240,6 +240,18 @@ class Monitor(val bus: Bus, val cpu: Cpu6502) {
return IVirtualMachine.MonitorCmdResult(disassem.first.single(), "a$${hexW(disassem.second)} ", false)
}
private fun parseRelativeToPC(relative: String, currentAddress: Int): Int {
val rest = relative.substring(1).trimStart()
if(rest.any()) {
return when(rest[0]) {
'-' -> currentAddress-parseNumber(rest.substring(1))
'+' -> currentAddress+parseNumber(rest.substring(1))
else -> throw Cpu6502.InstructionError("invalid address syntax")
}
}
return currentAddress
}
private fun parseNumber(number: String, decimalFirst: Boolean = false): Int {
val num = number.trim()
if (num.isBlank()) return 0