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fix for typo in setPSW

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folkert van heusden 2022-04-01 21:07:44 +02:00
parent 64220a64d7
commit 53a8c487b9
1 changed files with 7 additions and 4 deletions
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11
cpu.cpp
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@ -192,7 +192,7 @@ void cpu::setPSW(const uint16_t v, const bool limited)
if (limited) {
psw |= v & 0174000; // current & previous mode can only be increased, 11 can only be set
psw = 0174000; // retain upper 5 bit
psw &= 0174000; // retain upper 5 bit
psw |= v & ~0174000;
}
else {
@ -392,6 +392,8 @@ bool cpu::double_operand_instructions(const uint16_t instr)
uint16_t temp = (src_value - dst_value) & (word_mode ? 0xff : 0xffff);
// D(fprintf(stderr, "CMP%s %o,%o: %o\n", word_mode?"B":"", src_value, dst_value, temp);)
setPSW_n(SIGN(temp, word_mode));
setPSW_z(temp == 0);
setPSW_v(SIGN((src_value ^ dst_value) & (~dst_value ^ temp), word_mode));
@ -402,6 +404,7 @@ bool cpu::double_operand_instructions(const uint16_t instr)
case 0b011: { // BIT/BITB Bit Test Word/Byte
uint16_t dst_value = getGAM(dst_mode, dst_reg, word_mode, false);
//D(fprintf(stderr, "BIT%s: dst_value %o, src_val: %o\n", word_mode?"B":"", dst_value, src_value);)
uint16_t result = (dst_value & src_value) & (word_mode ? 0xff : 0xffff);
setPSW_n(SIGN(result, word_mode));
@ -1157,9 +1160,9 @@ bool cpu::single_operand_instructions(const uint16_t instr)
bool cpu::conditional_branch_instructions(const uint16_t instr)
{
const uint8_t opcode = (instr >> 8) & 255;
const int8_t offset = instr & 255;
bool take = false;
const uint8_t opcode = instr >> 8;
const int8_t offset = instr;
bool take = false;
switch(opcode) {
case 0b00000001: // BR