rlm@1: #include <cstring>
rlm@1: 
rlm@1: #include "GBA.h" // for SAVE_GAME_VERSION_3
rlm@1: #include "EEprom.h"
rlm@1: #include "../common/System.h"
rlm@1: #include "../common/Util.h"
rlm@1: 
rlm@1: extern int32 cpuDmaCount;
rlm@1: 
rlm@1: int32 eepromMode    = EEPROM_IDLE;
rlm@1: int32 eepromByte    = 0;
rlm@1: int32 eepromBits    = 0;
rlm@1: int32 eepromAddress = 0;
rlm@1: u8    eepromData[0x2000];
rlm@1: u8    eepromBuffer[16];
rlm@1: bool8 eepromInUse = false;
rlm@1: int32 eepromSize  = 512;
rlm@1: 
rlm@1: variable_desc eepromSaveData[] = {
rlm@1: 	{ &eepromMode,		sizeof(int32) },
rlm@1: 	{ &eepromByte,		sizeof(int32) },
rlm@1: 	{ &eepromBits,		sizeof(int32) },
rlm@1: 	{ &eepromAddress,	sizeof(int32) },
rlm@1: 	{ &eepromInUse,		sizeof(bool8) },
rlm@1: 	{ &eepromData[0],             512 },
rlm@1: 	{ &eepromBuffer[0],            16 },
rlm@1: 	{ NULL,							0 }
rlm@1: };
rlm@1: 
rlm@1: void eepromReset()
rlm@1: {
rlm@1: 	eepromMode    = EEPROM_IDLE;
rlm@1: 	eepromByte    = 0;
rlm@1: 	eepromBits    = 0;
rlm@1: 	eepromAddress = 0;
rlm@1: 	eepromInUse   = false;
rlm@1: 	eepromSize    = 512;
rlm@1: }
rlm@1: 
rlm@1: void eepromErase()
rlm@1: {
rlm@1: 	memset(eepromData, 0, 0x2000*sizeof(u8));
rlm@1: 	eepromMode    = EEPROM_IDLE;
rlm@1: 	eepromByte    = 0;
rlm@1: 	eepromBits    = 0;
rlm@1: 	eepromAddress = 0;
rlm@1: 	memset(eepromBuffer, 0, 16*sizeof(u8));
rlm@1: 	eepromInUse = false;
rlm@1: 	eepromSize  = 512;
rlm@1: }
rlm@1: 
rlm@1: void eepromSaveGame(gzFile gzFile)
rlm@1: {
rlm@1: 	utilWriteData(gzFile, eepromSaveData);
rlm@1: 	utilWriteInt(gzFile, eepromSize);
rlm@1: 	utilGzWrite(gzFile, eepromData, 0x2000);
rlm@1: }
rlm@1: 
rlm@1: void eepromReadGame(gzFile gzFile, int version)
rlm@1: {
rlm@1: 	utilReadData(gzFile, eepromSaveData);
rlm@1: 	if (version >= SAVE_GAME_VERSION_3)
rlm@1: 	{
rlm@1: 		eepromSize = utilReadInt(gzFile);
rlm@1: 		utilGzRead(gzFile, eepromData, 0x2000);
rlm@1: 	}
rlm@1: 	else
rlm@1: 	{
rlm@1: 		// prior to 0.7.1, only 4K EEPROM was supported
rlm@1: 		eepromSize = 512;
rlm@1: 	}
rlm@1: }
rlm@1: 
rlm@1: int eepromRead(u32 /* address */)
rlm@1: {
rlm@1: 	switch (eepromMode)
rlm@1: 	{
rlm@1: 	case EEPROM_IDLE:
rlm@1: 	case EEPROM_READADDRESS:
rlm@1: 	case EEPROM_WRITEDATA:
rlm@1: 		return 1;
rlm@1: 	case EEPROM_READDATA:
rlm@1: 	{
rlm@1: 		eepromBits++;
rlm@1: 		if (eepromBits == 4)
rlm@1: 		{
rlm@1: 			eepromMode = EEPROM_READDATA2;
rlm@1: 			eepromBits = 0;
rlm@1: 			eepromByte = 0;
rlm@1: 		}
rlm@1: 		return 0;
rlm@1: 	}
rlm@1: 	case EEPROM_READDATA2:
rlm@1: 	{
rlm@1: 		int data    = 0;
rlm@1: 		int address = eepromAddress << 3;
rlm@1: 		int mask    = 1 << (7 - (eepromBits & 7));
rlm@1: 		data = (eepromData[address+eepromByte] & mask) ? 1 : 0;
rlm@1: 		eepromBits++;
rlm@1: 		if ((eepromBits & 7) == 0)
rlm@1: 			eepromByte++;
rlm@1: 		if (eepromBits == 0x40)
rlm@1: 			eepromMode = EEPROM_IDLE;
rlm@1: 		return data;
rlm@1: 	}
rlm@1: 	default:
rlm@1: 		return 0;
rlm@1: 	}
rlm@1: 	return 1;
rlm@1: }
rlm@1: 
rlm@1: void eepromWrite(u32 /* address */, u8 value)
rlm@1: {
rlm@1: 	if (cpuDmaCount == 0)
rlm@1: 		return;
rlm@1: 	int bit = value & 1;
rlm@1: 	switch (eepromMode)
rlm@1: 	{
rlm@1: 	case EEPROM_IDLE:
rlm@1: 		eepromByte = 0;
rlm@1: 		eepromBits = 1;
rlm@1: 		eepromBuffer[eepromByte] = bit;
rlm@1: 		eepromMode = EEPROM_READADDRESS;
rlm@1: 		break;
rlm@1: 	case EEPROM_READADDRESS:
rlm@1: 		eepromBuffer[eepromByte] <<= 1;
rlm@1: 		eepromBuffer[eepromByte]  |= bit;
rlm@1: 		eepromBits++;
rlm@1: 		if ((eepromBits & 7) == 0)
rlm@1: 		{
rlm@1: 			eepromByte++;
rlm@1: 		}
rlm@1: 		if (cpuDmaCount == 0x11 || cpuDmaCount == 0x51)
rlm@1: 		{
rlm@1: 			if (eepromBits == 0x11)
rlm@1: 			{
rlm@1: 				eepromInUse   = true;
rlm@1: 				eepromSize    = 0x2000;
rlm@1: 				eepromAddress = ((eepromBuffer[0] & 0x3F) << 8) |
rlm@1: 				                ((eepromBuffer[1] & 0xFF));
rlm@1: 				if (!(eepromBuffer[0] & 0x40))
rlm@1: 				{
rlm@1: 					eepromBuffer[0] = bit;
rlm@1: 					eepromBits      = 1;
rlm@1: 					eepromByte      = 0;
rlm@1: 					eepromMode      = EEPROM_WRITEDATA;
rlm@1: 				}
rlm@1: 				else
rlm@1: 				{
rlm@1: 					eepromMode = EEPROM_READDATA;
rlm@1: 					eepromByte = 0;
rlm@1: 					eepromBits = 0;
rlm@1: 				}
rlm@1: 			}
rlm@1: 		}
rlm@1: 		else
rlm@1: 		{
rlm@1: 			if (eepromBits == 9)
rlm@1: 			{
rlm@1: 				eepromInUse   = true;
rlm@1: 				eepromAddress = (eepromBuffer[0] & 0x3F);
rlm@1: 				if (!(eepromBuffer[0] & 0x40))
rlm@1: 				{
rlm@1: 					eepromBuffer[0] = bit;
rlm@1: 					eepromBits      = 1;
rlm@1: 					eepromByte      = 0;
rlm@1: 					eepromMode      = EEPROM_WRITEDATA;
rlm@1: 				}
rlm@1: 				else
rlm@1: 				{
rlm@1: 					eepromMode = EEPROM_READDATA;
rlm@1: 					eepromByte = 0;
rlm@1: 					eepromBits = 0;
rlm@1: 				}
rlm@1: 			}
rlm@1: 		}
rlm@1: 		break;
rlm@1: 	case EEPROM_READDATA:
rlm@1: 	case EEPROM_READDATA2:
rlm@1: 		// should we reset here?
rlm@1: 		eepromMode = EEPROM_IDLE;
rlm@1: 		break;
rlm@1: 	case EEPROM_WRITEDATA:
rlm@1: 		eepromBuffer[eepromByte] <<= 1;
rlm@1: 		eepromBuffer[eepromByte]  |= bit;
rlm@1: 		eepromBits++;
rlm@1: 		if ((eepromBits & 7) == 0)
rlm@1: 		{
rlm@1: 			eepromByte++;
rlm@1: 		}
rlm@1: 		if (eepromBits == 0x40)
rlm@1: 		{
rlm@1: 			eepromInUse = true;
rlm@1: 			// write data;
rlm@1: 			for (int i = 0; i < 8; i++)
rlm@1: 			{
rlm@1: 				eepromData[(eepromAddress << 3) + i] = eepromBuffer[i];
rlm@1: 			}
rlm@1: 			systemSaveUpdateCounter = SYSTEM_SAVE_UPDATED;
rlm@1: 		}
rlm@1: 		else if (eepromBits == 0x41)
rlm@1: 		{
rlm@1: 			eepromMode = EEPROM_IDLE;
rlm@1: 			eepromByte = 0;
rlm@1: 			eepromBits = 0;
rlm@1: 		}
rlm@1: 		break;
rlm@1: 	}
rlm@1: }
rlm@1: