mirror of
https://github.com/hsoft/collapseos.git
synced 2024-11-24 01:28:06 +11:00
97a46a7b9b
My idea of plugging a RC2014 bridge directly onto a Sega Master System cartridge doesn't work. The SMS eats all I/O addr space, we can't use it. Therefore, this naive idea, in the emulator, of reusing sdc.c in sms.c as-is, doesn't work either. I'll have to find another way of communicating to a SPI device on the SMS. I'll probably do it through a controller port. Meanwhile, I need to decouple SPI from SDC in the emulator code so that I can reuse sdc.c. This is what is done here.
30 lines
1018 B
C
30 lines
1018 B
C
#include "emul.h"
|
|
|
|
typedef struct {
|
|
// Initialization status. 0 == not woken 8 == woken 9 == CMD0 received
|
|
// 10 == CMD8 received, 11 == CMD55 received, 12 == CMD41 received (fully
|
|
// initialized).
|
|
unsigned int initstat;
|
|
// We receive commands into this buffer.
|
|
byte recvbuf[6];
|
|
// Where the next SPI byte should be stored in recvbuf.
|
|
unsigned int recvidx;
|
|
// Buffer to the arguments for a response
|
|
byte sendbuf[5];
|
|
// Index of the next byte from sendbuf we should return. If -1, buffer is
|
|
// empty.
|
|
int sendidx;
|
|
// File used for contents read/write
|
|
FILE *fp;
|
|
// number of bytes read into the current CMD17. -1 means no CMD17 active.
|
|
int cmd17bytes;
|
|
// number of bytes received for the current CMD24. -2 means no CMD24 active.
|
|
// -1 means we're still waiting for the data token.
|
|
int cmd24bytes;
|
|
// running crc16 during read and write operations.
|
|
uint16_t crc16;
|
|
} SDC;
|
|
|
|
void sdc_init(SDC *sdc);
|
|
byte sdc_spix(SDC *sdc, byte val);
|