Гудвин, волшебник (29.09.2011 21:46, просмотров: 124) ответил koyodza на вроде 400кГц положено
Может быть и не 100 - лень вспоминать/думать ;) Проще было найти заведомо рабочий кусок кода (мега тактируется от встроенного генератора 8 МГц): /*-----------------------------------------------------------------------*/
/* Initialize Disk Drive */
/*-----------------------------------------------------------------------*/
DSTATUS disk_initialize (
BYTE drv /* Physical drive nmuber (0) */
)
{
BYTE n, ty, ocr[16];
SPCR = (1<<SPE)|(1<<MSTR)|(1<<SPR0); /* Enable SPI, Master, set clock rate fck/16 */
SPSR = 0b00000000; /* SPI.clk = SYSCLK/4 */
if (drv) return STA_NOINIT; /* Supports only single drive */
for (n = 10; n; n--) rcvr_spi(); /* 80 dummy clocks */
SELECT(); /* CS = L */
ty = 0;
if (send_cmd(CMD0, 0) == 1) { /* Enter Idle state */
Timer1 = 100; /* Initialization timeout of 1000 msec */
if (send_cmd(CMD8, 0x1AA) == 1) { /* SDC Ver2+ */
for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
if (ocr[2] == 0x01 && ocr[3] == 0xAA) { /* The card can work at vdd range of 2.7-3.6V */
do {
if (send_cmd(CMD55, 0) <= 1 && send_cmd(CMD41, 1UL << 30) == 0) break; /* ACMD41 with HCS bit */
} while (Timer1);
if (Timer1 && send_cmd(CMD58, 0) == 0) { /* Check CCS bit */
for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
ty = (ocr[0] & 0x40) ? 6 : 2;
}
}
} else { /* SDC Ver1 or MMC */
ty = (send_cmd(CMD55, 0) <= 1 && send_cmd(CMD41, 0) <= 1) ? 2 : 1; /* SDC : MMC */
do {
if (ty == 2) {
if (send_cmd(CMD55, 0) <= 1 && send_cmd(CMD41, 0) == 0) break; /* ACMD41 */
} else {
if (send_cmd(CMD1, 0) == 0) break; /* CMD1 */
}
} while (Timer1);
if (!Timer1 || send_cmd(CMD16, 512) != 0) /* Select R/W block length */
ty = 0;
}
}
CardType = ty;
DESELECT(); /* CS = H */
rcvr_spi(); /* Idle (Release DO) */
if (ty) { /* Initialization succeded */
Stat &= ~STA_NOINIT; /* Clear STA_NOINIT */
}
SPCR = 0b01010000; /* Initialize SPI port (Mode 0) */
SPSR = 0b00000001; /* SPI.clk = SYSCLK/2 */
return Stat;
}