Changeset 236

Timestamp:

10/17/08 01:02:27 (3 years ago)

Author:

auchtemm

Message:

added hdr2buf and buf2hdr functions, changed send_canmsg to use them

Files:

• trunk/electronics/avr/can/cannet.c (modified) (3 diffs)

trunk/electronics/avr/can/cannet.c

@@ -5 +5 @@
 
 
-/* txbuf is the address of TXBnCTRL */
-static void send_canmsg1(canmsg_t *msg, uint8_t txbuf)
+/* Maps canhdr_t to SIDH, SIDL, EID8 and EID0 
+ * buf must be large enough to hold 4 bytes
+ */
+static void hdr2buf(canhdr_t *hdr, uint8_t *buf)
 {
-        /* I'm on my 4th espresso in the past half hour, the following
-         * is likely riddled with errors.
-         */
-        mcp_write_byte(txbuf + 1, (msg->hdr.pri << 5) | (msg->hdr.class >> 3));
-        mcp_write_byte(txbuf + 2, (msg->hdr.class << 5) | (msg->hdr.dst >> 6) | (1 << 3));
-        mcp_write_byte(txbuf + 3, (msg->hdr.dst << 2) | ((msg->hdr.src >> 6) & 0x03));
-        mcp_write_byte(txbuf + 4, (msg->hdr.src << 3) | (msg->hdr.cmd & 0x07));
-        mcp_write_byte(txbuf + 5, msg->dlc);
-        mcp_write(txbuf + 6, msg->data, msg->dlc);
+        buf[0] = (hdr->pri << 5) | (hdr->class >> 3);
+        /* SIDL is a tricky bastard: 0bxxx0x0xx */
+        buf[1] = (hdr->class << 5) | (hdr->dst >> 6) | (1 << 3);
+        buf[2] = (hdr->dst << 2) | ((hdr->src >> 5) & 0x03);
+        buf[3] = (hdr->src << 3) | (hdr->cmd & 0x07);
 }
 
+static void buf2hdr(uint8_t *buf, canhdr_t *hdr)
+{
+        hdr->pri = buf[0] >> 5;
+        hdr->class = (buf[0] << 3) | (buf[1] >> 5);
+        hdr->dst = (buf[1] << 6) | (buf[2] >> 2);
+        hdr->src = ((buf[2] & 0x03) << 5) | (buf[3] >> 3);
+        hdr->cmd = buf[3] & 0x07;
+}
 
 
@@ -30 +36 @@
         uint8_t i;
         uint8_t reg;
+        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) {
-                        send_canmsg1(msg, i);
+
+                        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;
                 }
@@ -43 +55 @@
         return -1;
 }
+
+/* rxbuf is the address of RXBnCTRL */
+int8_t recv_canmsg(uint8_t rxbuf, canmsg_t *msg)
+{
+
+
+
+
+        return -1;
+}