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Fix PRGBank change logic & reset #55

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Fix PRGBank change logic & reset #55

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79 changes: 40 additions & 39 deletions Part #7 - Mappers & Basic Sounds/Mapper_004.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -51,7 +51,7 @@

Author
~~~~~~
David Barr, aka javidx9, �OneLoneCoder 2019
David Barr, aka javidx9, ©OneLoneCoder 2019
*/

#include "Mapper_004.h"
Expand Down Expand Up @@ -135,46 +135,47 @@ bool Mapper_004::cpuMapWrite(uint16_t addr, uint32_t &mapped_addr, uint8_t data)
{
// Update target register
pRegister[nTargetRegister] = data;
}

// Update Pointer Table
if (bCHRInversion)
{
pCHRBank[0] = pRegister[2] * 0x0400;
pCHRBank[1] = pRegister[3] * 0x0400;
pCHRBank[2] = pRegister[4] * 0x0400;
pCHRBank[3] = pRegister[5] * 0x0400;
pCHRBank[4] = (pRegister[0] & 0xFE) * 0x0400;
pCHRBank[5] = pRegister[0] * 0x0400 + 0x0400;
pCHRBank[6] = (pRegister[1] & 0xFE) * 0x0400;
pCHRBank[7] = pRegister[1] * 0x0400 + 0x0400;
}
else
{
pCHRBank[0] = (pRegister[0] & 0xFE) * 0x0400;
pCHRBank[1] = pRegister[0] * 0x0400 + 0x0400;
pCHRBank[2] = (pRegister[1] & 0xFE) * 0x0400;
pCHRBank[3] = pRegister[1] * 0x0400 + 0x0400;
pCHRBank[4] = pRegister[2] * 0x0400;
pCHRBank[5] = pRegister[3] * 0x0400;
pCHRBank[6] = pRegister[4] * 0x0400;
pCHRBank[7] = pRegister[5] * 0x0400;
}

if (bPRGBankMode)
{
pPRGBank[2] = (pRegister[6] & 0x3F) * 0x2000;
pPRGBank[0] = (nPRGBanks * 2 - 2) * 0x2000;
}
else
{
pPRGBank[0] = (pRegister[6] & 0x3F) * 0x2000;
pPRGBank[2] = (nPRGBanks * 2 - 2) * 0x2000;
}

pPRGBank[1] = (pRegister[7] & 0x3F) * 0x2000;
pPRGBank[3] = (nPRGBanks * 2 - 1) * 0x2000;
// Update Pointer Table
if (bCHRInversion)
{
pCHRBank[0] = pRegister[2] * 0x0400;
pCHRBank[1] = pRegister[3] * 0x0400;
pCHRBank[2] = pRegister[4] * 0x0400;
pCHRBank[3] = pRegister[5] * 0x0400;
pCHRBank[4] = (pRegister[0] & 0xFE) * 0x0400;
pCHRBank[5] = pRegister[0] * 0x0400 + 0x0400;
pCHRBank[6] = (pRegister[1] & 0xFE) * 0x0400;
pCHRBank[7] = pRegister[1] * 0x0400 + 0x0400;
}
else
{
pCHRBank[0] = (pRegister[0] & 0xFE) * 0x0400;
pCHRBank[1] = pRegister[0] * 0x0400 + 0x0400;
pCHRBank[2] = (pRegister[1] & 0xFE) * 0x0400;
pCHRBank[3] = pRegister[1] * 0x0400 + 0x0400;
pCHRBank[4] = pRegister[2] * 0x0400;
pCHRBank[5] = pRegister[3] * 0x0400;
pCHRBank[6] = pRegister[4] * 0x0400;
pCHRBank[7] = pRegister[5] * 0x0400;
}

uint8_t lPRGBanks = (nPRGBanks * 2 - 1);

if (bPRGBankMode)
{
pPRGBank[2] = (pRegister[6] & lPRGBanks) * 0x2000;
pPRGBank[0] = (nPRGBanks * 2 - 2) * 0x2000;
}
else
{
pPRGBank[0] = (pRegister[6] & lPRGBanks) * 0x2000;
pPRGBank[2] = (nPRGBanks * 2 - 2) * 0x2000;
}

pPRGBank[1] = (pRegister[7] & lPRGBanks) * 0x2000;
pPRGBank[3] = lPRGBanks * 0x2000;

return false;
}
Expand Down Expand Up @@ -303,7 +304,7 @@ void Mapper_004::reset()
nIRQReload = 0x0000;

for (int i = 0; i < 4; i++) pPRGBank[i] = 0;
for (int i = 0; i < 8; i++) { pCHRBank[i] = 0; pRegister[i] = 0; }
for (int i = 0; i < 8; i++) { pCHRBank[i] = 0; pRegister[i] = 0xFF; }

pPRGBank[0] = 0 * 0x2000;
pPRGBank[1] = 1 * 0x2000;
Expand Down