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c64load: emulate C64 KERNAL GETIN better

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no key is pressed
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Thomas Bernard 2019-12-31 19:16:11 +01:00
parent bf8347e4d9
commit d7451d6d6e
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GPG Key ID: 0FF11B67A5C0863C
1 changed files with 8 additions and 1 deletions
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9
src/c64load.c
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@ -102,13 +102,20 @@ static byte C64_mem_read(void *context, word address)
if ((c64->ram[1] & 2) && address >= 0xe000) if ((c64->ram[1] & 2) && address >= 0xe000)
{ {
GFX2_Log(GFX2_WARNING, "** ROM ** read($%04x)\n", address); GFX2_Log(GFX2_WARNING, "** ROM ** read($%04x)\n", address);
// $FFE4 GETIN
// make it return 0 (an Z=1) like if no key is pressed
if (address == 0xffe4) if (address == 0xffe4)
{
c64->keyjoyread++; c64->keyjoyread++;
return 0xA9; // LDA #$xx
}
if (address == 0xffe5)
return 0x00; // 2nd byte of LDA #$00
return 0x60; // RTS return 0x60; // RTS
} }
if ((c64->ram[1] & 4) && if ((c64->ram[1] & 4) &&
(address >= 0xd000) && (address < 0xe000)) (((address >= 0xd000) && (address < 0xd800)) || ((address >= 0xdc00) && (address < 0xe000))))
{ {
if ((address & 0xff00) == 0xd000) if ((address & 0xff00) == 0xd000)
{ {