Changeset 250

Timestamp:

10/21/08 17:09:28 (3 years ago)

Author:

auchtemm

Message:

fixed cannet_send.

Location:

trunk/electronics/avr/can

Files:

• cannet.c (modified) (1 diff)
• mcp.c (modified) (2 diffs)
• mcp.h (modified) (1 diff)

trunk/electronics/avr/can/cannet.c

@@ -34 +34 @@
 int8_t send_canmsg(canmsg_t *msg)
 {
-        uint8_t i;
-        uint8_t reg;
+        uint8_t stat;
+        uint8_t rts;
+        uint8_t txbuf;
         uint8_t hdrbuf[4];
 
-        /* TODO: rewrite this to use load tx buffer */
-        for (i = TXB0CTRL; i <= TXB0CTRL + 0x20; i += 0x10) {
-                mcp_read(i, &reg, 1);
-                if ((reg & (1 << 3)) == 0) {
+        stat = mcp_read_stat();
+        txbuf = 0;
+        rts = 0;
+        
+        /* See fig. 12-8 in MCP2515 datasheet. */
+        rts |= !!(stat & (1 << 2));
+        rts |= !!(stat & (1 << 4)) << 1;
+        rts |= !!(stat & (1 << 6)) << 2;
 
-                        hdr2buf(&msg->hdr, hdrbuf);
-                        mcp_write(i + 1, hdrbuf, 4);
-                        reg |= 1 << 3;
-                        mcp_write_byte(i, reg);
-                        mcp_write_byte(i + 5, msg->dlc);
-                        mcp_write(i + 6, msg->data, msg->dlc);
-                        return 0;
-                }
+        if (rts == 7)
+                return -1;
+
+        if ((rts & 1) == 0) {
+                txbuf = TXBUF0;
+                rts |= 1;
+        } else if ((rts & 2) == 0) {
+                txbuf = TXBUF1;
+                rts |= 2;
+        } else {
+                txbuf = TXBUF2;
+                rts |= 4;
         }
 
-        return -1;
+        hdr2buf(&msg->hdr, hdrbuf);
+
+        mcp_load_txbuf(txbuf, hdrbuf, 4);
+        mcp_load_txbuf(txbuf + 1, msg->data, msg->dlc);
+        mcp_rts(rts);
+
+        return 0;
 }
+
 
 /* rxbuf is the address of RXBnCTRL */

trunk/electronics/avr/can/mcp.c

@@ -39 +39 @@
         addr &= 0x03;
         clrbit(CSP, CS);
-        spi_send(MCPRXBUF | (addr << 1));
+        spi_send(MCPRXBUF | ((addr & 0x03) << 1));
         for (i = 0; i < nbuf; i++) {
                 buf[i] = spi_recv();
@@ -74 +74 @@
         addr &= 0x07;
         clrbit(CSP, CS);
-        spi_send(MCPTXBUF | addr);
+        spi_send(MCPTXBUF | (addr & 0x07));
         for (i = 0; i < nbuf; i++) {
                 spi_send(buf[i]);

trunk/electronics/avr/can/mcp.h

@@ -65 +65 @@
 
 
+/* for mcp_read_rxbuf
+ * D suffix is data only
+ */
+enum {
+        RXBUF0 = 0,
+        RXBUF0D,
+        RXBUF1 = 2,
+        RXBUF1D,
+};
+
+/* For mcp_load_txbuf */
+enum {
+        TXBUF0 = 0,
+        TXBUF0D,
+        TXBUF1,
+        TXBUF1D,
+        TXBUF2,
+        TXBUF2D,
+};