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Rewrite mappers 162,163,164; add mapper 558. Add EEPROM support to 164.

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This commit is contained in:
NewRisingSun
2021-05-30 01:08:41 +02:00
parent 597175043b
commit 97ffbc5f83
10 changed files with 442 additions and 200 deletions
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135
src/boards/eeprom_93C66.c Normal file
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#include "eeprom_93C66.h"
uint8* eeprom_93C66_storage;
uint8 eeprom_93C66_opcode;
uint8 eeprom_93C66_data;
uint16 eeprom_93C66_address;
uint8 eeprom_93C66_state;
uint8 eeprom_93C66_lastCLK;
uint8 eeprom_93C66_writeEnabled;
uint8 eeprom_93C66_output;
#define OPCODE_MISC 0
#define OPCODE_WRITE 1
#define OPCODE_READ 2
#define OPCODE_ERASE 3
#define OPCODE_WRITEDISABLE 10
#define OPCODE_WRITEALL 11
#define OPCODE_ERASEALL 12
#define OPCODE_WRITEENABLE 13
#define STATE_STANDBY 0
#define STATE_STARTBIT 1
#define STATE_OPCODE 3
#define STATE_ADDRESS 12
#define STATE_DATA 20
#define STATE_FINISHED 99
void eeprom_93C66_init ()
{
eeprom_93C66_address =0;
eeprom_93C66_state =STATE_STANDBY;
eeprom_93C66_lastCLK =0;
eeprom_93C66_writeEnabled =0;
}
uint8 eeprom_93C66_read ()
{
return eeprom_93C66_output;
}
void eeprom_93C66_write (uint8 CS, uint8 CLK, uint8 DAT)
{
if (!CS && eeprom_93C66_state <= STATE_ADDRESS)
eeprom_93C66_state =STATE_STANDBY;
else
if (eeprom_93C66_state ==STATE_STANDBY && CS && CLK)
{
eeprom_93C66_state =STATE_STARTBIT;
eeprom_93C66_opcode =0;
eeprom_93C66_address =0;
eeprom_93C66_output =1;
}
else
if (CLK && !eeprom_93C66_lastCLK)
{
if (eeprom_93C66_state >=STATE_STARTBIT && eeprom_93C66_state <STATE_OPCODE)
eeprom_93C66_opcode =(eeprom_93C66_opcode <<1) | (DAT? 1: 0);
else
if (eeprom_93C66_state >=STATE_OPCODE && eeprom_93C66_state <STATE_ADDRESS)
eeprom_93C66_address =(eeprom_93C66_address <<1) | (DAT? 1: 0);
else
if (eeprom_93C66_state >=STATE_ADDRESS && eeprom_93C66_state <STATE_DATA)
{
if (eeprom_93C66_opcode ==OPCODE_WRITE || eeprom_93C66_opcode ==OPCODE_WRITEALL)
eeprom_93C66_data =(eeprom_93C66_data <<1) | (DAT? 1: 0);
else
if (eeprom_93C66_opcode ==OPCODE_READ)
{
eeprom_93C66_output =!!(eeprom_93C66_data &0x80);
eeprom_93C66_data = eeprom_93C66_data <<1;
}
}
eeprom_93C66_state++;
if (eeprom_93C66_state ==STATE_ADDRESS) {
switch (eeprom_93C66_opcode)
{
case OPCODE_MISC:
eeprom_93C66_opcode =(eeprom_93C66_address >>7) + 10;
switch (eeprom_93C66_opcode)
{
case OPCODE_WRITEDISABLE:
eeprom_93C66_writeEnabled = 0;
eeprom_93C66_state = STATE_FINISHED;
break;
case OPCODE_WRITEENABLE:
eeprom_93C66_writeEnabled = 1;
eeprom_93C66_state = STATE_FINISHED;
break;
case OPCODE_ERASEALL:
if (eeprom_93C66_writeEnabled) for (int i =0; i <512; i++) eeprom_93C66_storage[i] = 0xFF;
eeprom_93C66_state = STATE_FINISHED;
break;
case OPCODE_WRITEALL:
eeprom_93C66_address = 0;
break;
}
break;
case OPCODE_ERASE:
if (eeprom_93C66_writeEnabled) eeprom_93C66_storage[eeprom_93C66_address] = 0xFF;
eeprom_93C66_state = STATE_FINISHED;
break;
case OPCODE_READ:
eeprom_93C66_data = eeprom_93C66_storage[eeprom_93C66_address++];
break;
}
}
else
if (eeprom_93C66_state ==STATE_DATA)
{
if (eeprom_93C66_opcode ==OPCODE_WRITE)
{
eeprom_93C66_storage[eeprom_93C66_address++] = eeprom_93C66_data;
eeprom_93C66_state = STATE_FINISHED;
}
else
if (eeprom_93C66_opcode ==OPCODE_WRITEALL)
{
eeprom_93C66_storage[eeprom_93C66_address++] = eeprom_93C66_data;
eeprom_93C66_state = CS && eeprom_93C66_address <512? STATE_ADDRESS: STATE_FINISHED;
}
else
if (eeprom_93C66_opcode ==OPCODE_READ)
{
if (eeprom_93C66_address <512) eeprom_93C66_data = eeprom_93C66_storage[eeprom_93C66_address];
eeprom_93C66_state = CS && ++eeprom_93C66_address <=512? STATE_ADDRESS: STATE_FINISHED;
}
}
if (eeprom_93C66_state == STATE_FINISHED)
{
eeprom_93C66_output = 0;
eeprom_93C66_state = STATE_STANDBY;
}
}
eeprom_93C66_lastCLK = CLK;
}