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CLR/CLRB fix

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This commit is contained in:
folkert van heusden 2023-03-18 22:56:08 +01:00
parent 488bb55cec
commit b035260e07
Signed by untrusted user who does not match committer: folkert
GPG key ID: 6B6455EDFEED3BD1
2 changed files with 20 additions and 9 deletions
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11
bus.cpp
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@ -268,10 +268,17 @@ uint16_t bus::read(const uint16_t a, const bool word_mode, const bool use_prev,
return system_size;
}
if (!peek_only) {
if (a & 1)
DOLOG(debug, !peek_only, "bus::readWord: odd address UNHANDLED %o", a);
DOLOG(debug, true, "bus::readWord: odd address UNHANDLED %o", a);
DOLOG(debug, !peek_only, "UNHANDLED read %o(%c)", a, word_mode ? 'B' : ' ');
DOLOG(debug, true, "UNHANDLED read %o(%c)", a, word_mode ? 'B' : ' ');
// DEBUG CODE TODO
extern FILE *lfh;
fflush(lfh);
assert(false);
}
return -1;
}

12
cpu.cpp
View file

@ -351,9 +351,9 @@ gam_rc_t cpu::getGAM(const uint8_t mode, const uint8_t reg, const bool word_mode
break;
case 3:
g.addr = b->read(getRegister(reg, g.set, prev_mode), false, prev_mode, g.space);
addRegister(reg, prev_mode, 2);
if (read_value)
g.value = b->read(g.addr.value(), word_mode, prev_mode, false, d_space);
addRegister(reg, prev_mode, 2);
break;
case 4:
addRegister(reg, prev_mode, !word_mode || reg == 7 || reg == 6 ? -2 : -1);
@ -770,16 +770,20 @@ bool cpu::single_operand_instructions(const uint16_t instr)
case 0b000101000: { // CLR/CLRB
{
auto g_dst = getGAM(dst_mode, dst_reg, word_mode, false);
auto g_dst = getGAMAddress(dst_mode, dst_reg, word_mode);
uint16_t r = 0;
// CLRB only clears the least significant byte
if (word_mode)
r = g_dst.value.value() & 0xff00;
if (word_mode) {
if (dst_mode)
r = b->read(g_dst.addr.value(), false, false) & 0xff00;
else
r = getRegister(dst_reg, false, false) & 0xff00;
// both in byte and word mode the full register must be updated
g_dst.word_mode = false;
}
bool set_flags = putGAM(g_dst, r);