diff options
Diffstat (limited to 'demos/ARM7-LPC214x-GCC/mmcsd.c')
-rw-r--r-- | demos/ARM7-LPC214x-GCC/mmcsd.c | 180 |
1 files changed, 152 insertions, 28 deletions
diff --git a/demos/ARM7-LPC214x-GCC/mmcsd.c b/demos/ARM7-LPC214x-GCC/mmcsd.c index 1c0d5c7d8..7867782c9 100644 --- a/demos/ARM7-LPC214x-GCC/mmcsd.c +++ b/demos/ARM7-LPC214x-GCC/mmcsd.c @@ -26,11 +26,64 @@ static EventSource MMCInsertEventSource;
+/*
+ * Subsystem initialization.
+ */
void InitMMC(void) {
chEvtInit(&MMCInsertEventSource);
}
+static void sendhdr(BYTE8 cmd, ULONG32 arg) {
+ BYTE8 buf[6];
+
+ /*
+ * Wait for the bus to become idle if a write operation was in progress.
+ */
+ while (TRUE) {
+ sspRW(buf, NULL, 1);
+ if (buf[0] == 0xFF)
+ break;
+#ifdef NICE_WAITING
+ chThdSleep(1); /* Trying to be nice with the other threads.*/
+#endif
+ }
+
+ buf[0] = 0x40 | cmd;
+ buf[1] = arg >> 24;
+ buf[2] = arg >> 16;
+ buf[3] = arg >> 8;
+ buf[4] = arg;
+ buf[5] = 0x95; /* Valid for CMD0 ingnored by other commands. */
+ sspRW(NULL, buf, 6);
+}
+
+static BYTE8 recvr1(void) {
+ int i;
+ BYTE8 r1[1];
+
+ for (i = 0; i < 9; i++) {
+ sspRW(r1, NULL, 1);
+ if (r1[0] != 0xFF)
+ return r1[0];
+ }
+ return 0xFF; /* Timeout.*/
+}
+
+static BOOL getdata(BYTE8 *buf, ULONG32 n) {
+ int i;
+
+ for (i = 0; i < MMC_WAIT_DATA; i++) {
+ sspRW(buf, NULL, 1);
+ if (buf[0] == 0xFE) {
+ sspRW(buf, NULL, n);
+ sspRW(NULL, NULL, 2); /* CRC ignored.*/
+ return FALSE;
+ }
+ }
+ return TRUE; /* Timeout.*/
+}
+
/*
* Initializes a card after the power up by selecting the SPI mode.
*/
@@ -47,7 +100,7 @@ BOOL mmcInit(void) { sspRW(NULL, NULL, 16); /* 128 clock pulses without ~CS asserted. */
int i = 0;
while (TRUE) {
- if (mmcSendCommand(0, 0) == 0x01)
+ if (mmcSendCommand(CMDGOIDLE, 0) == 0x01)
break;
if (++i >= CMD0_RETRY)
return TRUE;
@@ -59,7 +112,7 @@ BOOL mmcInit(void) { */
i = 0;
while (TRUE) {
- BYTE8 b = mmcSendCommand(1, 0);
+ BYTE8 b = mmcSendCommand(CMDINIT, 0);
if (b == 0x00)
break;
if (b != 0x01)
@@ -76,32 +129,6 @@ BOOL mmcInit(void) { return FALSE;
}
-static void sendhdr(BYTE8 cmd, ULONG32 arg) {
- BYTE8 buf[8];
-
- buf[0] = 0xFF;
- buf[1] = 0x40 | cmd;
- buf[2] = arg >> 24;
- buf[3] = arg >> 16;
- buf[4] = arg >> 8;
- buf[5] = arg;
- buf[6] = 0x95; /* Valid for CMD0 ingnored by other commands. */
- buf[7] = 0xFF;
- sspRW(NULL, buf, 8);
-}
-
-static BYTE8 recvr1(void) {
- int i;
- BYTE8 r1[1];
-
- for (i = 0; i < 8; i++) {
- sspRW(r1, NULL, 1);
- if (r1[0] != 0xFF)
- return r1[0];
- }
- return 0xFF;
-}
-
/*
* Sends a simple command and returns a R1-type response.
*/
@@ -114,3 +141,100 @@ BYTE8 mmcSendCommand(BYTE8 cmd, ULONG32 arg) { sspReleaseBus();
return r1;
}
+
+/*
+ * Reads the card info record.
+ * @param data the pointer to a \p MMCCSD structure
+ * @return \p TRUE if an error happened
+ */
+BOOL mmcGetSize(MMCCSD *data) {
+ BYTE8 buf[16];
+
+ sspAcquireBus();
+ sendhdr(CMDREADCSD, 0);
+ if (recvr1() != 0x00) {
+ sspReleaseBus();
+ return TRUE;
+ }
+ if (getdata(buf, 16)) {
+ sspReleaseBus();
+ return TRUE;
+ }
+ sspReleaseBus();
+
+ /* csize * multiplier */
+ data->csize = (((buf[6] & 3) << 10) | (buf[7] << 2) | (buf[8] >> 6)) *
+ (1 << (2 + (((buf[9] & 3) << 1) | (buf[10] >> 7))));
+ data->rdblklen = 1 << (buf[5] & 15);
+ return FALSE;
+}
+
+/*
+ * Reads a block.
+ * @param blknum the block number
+ * @param buf the pointer to the read buffer
+ * @return \p TRUE if an error happened
+ */
+BOOL mmcBlockRead(ULONG32 blknum, BYTE8 *buf) {
+
+ sspAcquireBus();
+ sendhdr(CMDREAD, blknum << 8);
+ if (recvr1() != 0x00) {
+ sspReleaseBus();
+ return TRUE;
+ }
+ if (getdata(buf, 512)) {
+ sspReleaseBus();
+ return TRUE;
+ }
+ sspReleaseBus();
+ return FALSE;
+}
+
+/*
+ * Writes a block.
+ * @param blknum the block number
+ * @param buf the pointer to the write buffer
+ * @return \p TRUE if an error happened
+ * @note The function DOES NOT wait for the SPI bus to become free after
+ * sending the data, the bus check is done before sending commands to
+ * the card, this allows to not make useless busy waiting. The invoking
+ * thread can do other things while the data is being written.
+ */
+BOOL mmcBlockWrite(ULONG32 blknum, BYTE8 *buf) {
+ static BYTE8 start[] = {0xFF, 0xFE};
+ BYTE8 b[4];
+
+ sspAcquireBus();
+ sendhdr(CMDWRITE, blknum << 8);
+ if (recvr1() != 0x00) {
+ sspReleaseBus();
+ return TRUE;
+ }
+ sspRW(NULL, start, 2); /* Data prologue.*/
+ sspRW(NULL, buf, 512); /* Data.*/
+ sspRW(NULL, NULL, 2); /* CRC ignored in this version.*/
+ sspRW(b, NULL, 1);
+ sspReleaseBus();
+ if ((b[0] & 0x1E) != 0x05)
+ return TRUE;
+ return FALSE;
+}
+
+/*
+ * Makes sure that pending operations are completed before returning.
+ */
+void mmcSynch(void) {
+ BYTE8 buf[4];
+
+ sspAcquireBus();
+ while (TRUE) {
+ sspRW(buf, NULL, 1);
+ if (buf[0] == 0xFF)
+ break;
+#ifdef NICE_WAITING
+ chThdSleep(1); /* Trying to be nice with the other threads.*/
+#endif
+ }
+ sspReleaseBus();
+}
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