Diff: seeed_can_api.cpp

Revision:

1:ad71faa09868

Parent:

0:f5d099885d3d

Child:

2:fd026fcfde94

--- a/seeed_can_api.cpp	Tue Nov 05 22:37:35 2013 +0000
+++ b/seeed_can_api.cpp	Wed Nov 06 20:16:11 2013 +0000
@@ -42,20 +42,16 @@
     for (uint32_t i = 0; i < 3; i++) {                                  // Clear all CAN TX buffers
         mcpWriteMultiple(obj, canBuffer[i], y, sizeof(x) );             // using empty CAN message (as an array)
     }
-    mcpWrite(obj, MCP_CANINTE, MCP_RX0IF | MCP_RX1IF);                  // RX buffers can generate a interrupt
-#if (DEBUG_RXANY==1)
-    // enable both receive-buffers to receive any message and enable rollover
-    mcpBitModify(obj, MCP_RXB0CTRL, MCP_RXB_RX_MASK | MCP_RXB_BUKT_MASK, MCP_RXB_RX_ANY | MCP_RXB_BUKT_MASK);
-    mcpBitModify(obj, MCP_RXB1CTRL, MCP_RXB_RX_MASK, MCP_RXB_RX_ANY);
-#else
-    // enable both receive-buffers to receive messages with std. and ext. identifiers and enable rollover
+    // enable both receive-buffers, using filters to receive messages with std. and ext. identifiers that meet the filter criteria and enable rollover from RXB0 to RXB1 if RXB0 is full
     mcpBitModify(obj, MCP_RXB0CTRL, MCP_RXB_RX_MASK | MCP_RXB_BUKT_MASK, MCP_RXB_RX_STDEXT | MCP_RXB_BUKT_MASK );
     mcpBitModify(obj, MCP_RXB1CTRL, MCP_RXB_RX_MASK, MCP_RXB_RX_STDEXT);
-#endif
 #ifdef DEBUG
     printf("Setting bit rate\r\n");
 #endif
-    return (mcpSetBitRate(obj, bitRate)) ? 1 : 0;                       // set baudrate and return
+    if (!mcpSetBitRate(obj, bitRate)) {                                 // set baudrate
+        return 0;
+    }
+    return mcpSetMode(obj, MODE_NORMAL) ? 1 : 0;                        // set Normal mode and return
 }
 
 /**  set MCP2515 operation mode
@@ -130,14 +126,15 @@
     uint32_t bestCanRate = 0;
     uint32_t minBRP = (MCP_CLOCK_FREQ / (2 * MCP_MAX_TIME_QUANTA * bitRate));
     uint32_t maxBRP = (MCP_CLOCK_FREQ / (2 * MCP_MIN_TIME_QUANTA * bitRate));
-    
-    #ifdef DEBUG
-        printf("Setting configuration mode\r\n");
-    #endif
-        if(!mcpSetMode(obj, MODE_CONFIG)) {                                      // Go into configuration mode
-            return 0;
-        }
-    
+
+#ifdef DEBUG
+    printf("Setting configuration mode\r\n");
+#endif
+    uint8_t initialMode = mcpRead(obj, MCP_CANCTRL) & MODE_MASK;        // Store the current operation mode
+    if(!mcpSetMode(obj, MODE_CONFIG)) {                             // Go into configuration mode
+        return 0;
+    }
+
     for (uint32_t i = 0; i < sizeof(x); i++) y[i] = NULL;               // Initialise CANtiming (btlmode, sjw and sam all = 0)
     if ((bitRate < CAN_MIN_RATE) || (bitRate > CAN_MAX_RATE)) {
 #ifdef DEBUG
@@ -171,7 +168,7 @@
     printf("Syncseg: 1\tPropSeg: %d\tPhaseSeg1: %d\tPhaseSeg2: %d\r\n", (x.prseg+1), (x.phseg1+1), (x.phseg1+1));
     printf("Setting normal mode\r\n");
 #endif
-    return (mcpSetMode(obj, MODE_NORMAL)) ? 1 : 0;                      // desired bit rate set enter normal mode and return
+    return (mcpSetMode(obj, initialMode)) ? 1 : 0;                      // desired bit rate set enter normal mode and return
 }
 
 /** write a CAN id to a mask, filter or transmit buffer
@@ -322,11 +319,12 @@
 #ifdef DEBUG
     printf("Begin to set Mask!!\r\n");
 #endif
+    uint8_t initialMode = mcpRead(obj, MCP_CANCTRL) & MODE_MASK;        // Store the current operation mode
     if(!mcpSetMode(obj, MODE_CONFIG)) {
         return 0;
     }
     mcpWriteId(obj, mask[num], ext, ulData);
-    if(!mcpSetMode(obj, MODE_NORMAL)) {
+    if(!mcpSetMode(obj, initialMode)) {
         return 0;
     }
 #ifdef DEBUG
@@ -350,11 +348,12 @@
 #ifdef DEBUG
     printf("Begin to set Filter!!\r\n");
 #endif
+    uint8_t initialMode = mcpRead(obj, MCP_CANCTRL) & MODE_MASK;        // Store the current operation mode
     if(!mcpSetMode(obj, MODE_CONFIG)) {
         return 0;
     }
     mcpWriteId(obj, filter[num], ext, ulData);
-    if(!mcpSetMode(obj, MODE_NORMAL)) {
+    if(!mcpSetMode(obj, initialMode)) {
         return 0;
     }
 #ifdef DEBUG