Support reading game/save using MMM01

This commit is contained in:
splash5 2022-05-14 15:22:05 +08:00
parent 6a39746732
commit 77eace5937

View File

@ -365,9 +365,10 @@ void setup_GB() {
// Set Control Pins to Output RST(PH0) CLK(PH1) CS(PH3) WR(PH5) RD(PH6)
DDRH |= (1 << 0) | (1 << 1) | (1 << 3) | (1 << 5) | (1 << 6);
// Output a high signal on all pins, pins are active low therefore everything is disabled now
PORTH |= (1 << 0) | (1 << 3) | (1 << 5) | (1 << 6);
PORTH |= (1 << 3) | (1 << 5) | (1 << 6);
// Output a low signal on CLK(PH1) to disable writing GB Camera RAM
PORTH &= ~(1 << 1);
// Output a low signal on RST(PH0) to initialize MMC correctly
PORTH &= ~((1 << 0) | (1 << 1));
// Set Data Pins (D0-D7) to Input
DDRC = 0x00;
@ -376,9 +377,24 @@ void setup_GB() {
delay(400);
// RST(PH0) to H
PORTH |= (1 << 0);
// Print start page
getCartInfo_GB();
showCartInfo_GB();
// MMM01 initialize
if (romType >= 11 && romType <= 13)
{
dataOut();
writeByte_GB(0x3fff, 0x00);
writeByte_GB(0x5fff, 0x40);
writeByte_GB(0x7fff, 0x01);
writeByte_GB(0x1fff, 0x3a);
writeByte_GB(0x1fff, 0x7a);
dataIn_GB();
}
}
void showCartInfo_GB() {
@ -694,7 +710,9 @@ void getCartInfo_GB() {
}
// Get Checksum as string
sprintf(checksumStr, "%02X%02X", readByte_GB(0x014E), readByte_GB(0x014F));
eepbit[6] = readByte_GB(0x014E);
eepbit[7] = readByte_GB(0x014F);
sprintf(checksumStr, "%02X%02X", eepbit[6], eepbit[7]);
// Get name
byte myByte = 0;
@ -750,9 +768,38 @@ void readROM_GB() {
// Switch data pins to output
dataOut();
// Second bank starts at 0x4000
if (currBank > 1) {
romAddress = 0x4000;
}
// Set ROM bank for MBC2/3/4/5
if (romType >= 5) {
writeByte_GB(0x2100, currBank);
if (romType >= 11 && romType <= 13) {
if ((currBank & 0x1f) == 0) {
// reset MMM01
PORTH &= ~(1 << 0);
PORTH |= (1 << 0);
// remap to higher 4Mbits ROM
writeByte_GB(0x3fff, 0x20);
writeByte_GB(0x5fff, 0x40);
writeByte_GB(0x7fff, 0x01);
writeByte_GB(0x1fff, 0x3a);
writeByte_GB(0x1fff, 0x7a);
// for every 4Mbits ROM, restart from 0x0000
romAddress = 0x0000;
currBank++;
}
else {
writeByte_GB(0x6000, 0);
writeByte_GB(0x2000, (currBank & 0x1f));
}
}
else {
writeByte_GB(0x2100, currBank);
}
}
// Set ROM bank for MBC1
else {
@ -764,11 +811,6 @@ void readROM_GB() {
// Switch data pins to intput
dataIn_GB();
// Second bank starts at 0x4000
if (currBank > 1) {
romAddress = 0x4000;
}
// Read banks and save to SD
while (romAddress <= 0x7FFF) {
for (int i = 0; i < 512; i++) {
@ -807,8 +849,8 @@ unsigned int calc_checksum_GB (char* fileName, char* folder) {
myFile.close();
sd.chdir();
// Subtract checksum bytes
calcChecksum -= readByte_GB(0x014E);
calcChecksum -= readByte_GB(0x014F);
calcChecksum -= eepbit[6];
calcChecksum -= eepbit[7];
// Return result
return (calcChecksum);
@ -883,7 +925,7 @@ void readSRAM_GB() {
readByte_GB(0x0134);
dataOut();
if (romType <= 4) {
if (romType <= 4 || (romType >= 11 && romType <= 13)) {
writeByte_GB(0x6000, 1);
}
@ -942,7 +984,7 @@ void writeSRAM_GB() {
dataOut();
// Enable SRAM for MBC1
if (romType <= 4) {
if (romType <= 4 || (romType >= 11 && romType <= 13)) {
writeByte_GB(0x6000, 1);
}