diff options
| author | Camil Staps | 2017-01-31 23:15:28 +0100 |
|---|---|---|
| committer | Camil Staps | 2017-01-31 23:15:28 +0100 |
| commit | 631204a1feffa8cf3795060370b14dfb9f53f533 (patch) | |
| tree | 001d32e0157127607f7c088881f098c2eca841a1 /diskio.c | |
Diffstat (limited to 'diskio.c')
| -rw-r--r-- | diskio.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/diskio.c b/diskio.c new file mode 100644 index 0000000..ba12e4a --- /dev/null +++ b/diskio.c @@ -0,0 +1,109 @@ +/*-----------------------------------------------------------------------*/
+/* Low level disk I/O module skeleton for Petit FatFs (C)ChaN, 2014 */
+/*-----------------------------------------------------------------------*/
+
+#include "diskio.h"
+#include "sd.h"
+#include "spi.h"
+#include "util.h"
+
+static void spi_rx_multi(BYTE *buff, UINT cnt) {
+ do {
+ *buff++ = spi_rx();
+ } while (--cnt);
+}
+
+static int rcv_datablock(BYTE *buff, UINT btr) {
+ uint8_t token;
+ uint16_t count = 10000;
+
+ do token = spi_rx(); while (token == 0xff && --count);
+
+ if (token != 0xfe)
+ return 0;
+
+ spi_rx_multi(buff, btr);
+ spi_rx();
+ spi_rx();
+
+ return 1;
+}
+
+/*-----------------------------------------------------------------------*/
+/* Initialize Disk Drive */
+/*-----------------------------------------------------------------------*/
+
+static DSTATUS status = STA_NODISK;
+
+DSTATUS disk_status(BYTE pdrv) {
+ if (pdrv)
+ return STA_NOINIT;
+ return status;
+}
+
+DSTATUS disk_initialize (BYTE pdrv)
+{
+ uint8_t n, cmd;
+ uint32_t tmr;
+
+ if (!status)
+ return 0;
+
+#ifdef DEBUG
+ printf("Init SD\r\n");
+#endif
+
+ if (sd_init())
+ return STA_NOINIT;
+
+#ifdef DEBUG
+ printf("Done disk_initialize\r\n");
+#endif
+
+ status = 0;
+
+ return 0;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Read Partial Sector */
+/*-----------------------------------------------------------------------*/
+
+DRESULT disk_read (
+ BYTE pdrv, /* Physical drive number (0) */
+ BYTE* buff, /* Pointer to the destination object */
+ DWORD sector, /* Sector number (LBA) */
+ UINT count /* Byte count (bit15:destination) */
+)
+{
+ DRESULT res = RES_ERROR;
+ BYTE rc;
+ UINT bc;
+
+ if (pdrv || !count)
+ return RES_PARERR;
+ if (status && STA_NOINIT)
+ return RES_NOTRDY;
+
+ sector *= 512;
+
+ if (count == 1) {
+ if ((sd_send_command(SD_READ_SINGLE_BLOCK, sector) == 0)
+ && rcv_datablock(buff, 512))
+ count = 0;
+ } else if (sd_send_command(SD_READ_MULTIPLE_BLOCK, sector) == 0) {
+ do {
+ if (!rcv_datablock(buff, 512))
+ break;
+ buff += 512;
+ } while (--count);
+ sd_send_command(SD_STOP_TRANSMISSION, 0);
+ }
+
+ SD_DESELECT();
+ spi_rx();
+
+ return count ? RES_ERROR : RES_OK;
+}
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