Simple C_CAN test on LPC11C24

libuavcan_drivers/lpc11c24/test_olimex_lpc_p11c24/src/main.cpp

@@ -3,49 +3,134 @@
  */
 
 #include <board.hpp>
+#include <chip.h>
 
-struct A
+namespace
 {
-    A()
-    {
-        board::setStatusLed(true);
-        board::setErrorLed(false);
-    }
 
-    ~A()
-    {
-        board::setStatusLed(false);
-        board::setErrorLed(true);
-    }
-};
+CCAN_MSG_OBJ_T msg_obj;
 
-static A a;
-
-static long long zero_global;
-
-static long long non_zero_global = 123456789123456789;
-
-static long long post_initialized_global;
-
-__attribute__((constructor))
-static void foo()
+extern "C"
 {
-    post_initialized_global = 987654321987654321;
+
+void can_rx_callback(uint8_t msg_obj_num)
+{
+    msg_obj.msgobj = msg_obj_num;
+    LPC_CCAN_API->can_receive(&msg_obj);
+    if (msg_obj_num == 1)
+    {
+        msg_obj.msgobj = 2;
+        msg_obj.mode_id += 0x100;
+        LPC_CCAN_API->can_transmit(&msg_obj);
+    }
 }
 
+void can_tx_callback(uint8_t msg_obj_num)
+{
+    (void)msg_obj_num;
+}
+
+void can_error_callback(uint32_t error_info)
+{
+    (void)error_info;
+}
+
+void CAN_IRQHandler(void)
+{
+    LPC_CCAN_API->isr();
+}
+
+} // extern "C"
+
+bool calculateCanBaudrate(uint32_t baud_rate, uint32_t can_api_timing_cfg[2])
+{
+    const uint32_t pclk = Chip_Clock_GetMainClockRate();
+    const uint32_t clk_per_bit = pclk / baud_rate;
+    for (uint32_t div = 0; div <= 15; div++)
+    {
+        for (uint32_t quanta = 1; quanta <= 32; quanta++)
+        {
+            for (uint32_t segs = 3; segs <= 17; segs++)
+            {
+                if (clk_per_bit == (segs * quanta * (div + 1)))
+                {
+                    segs -= 3;
+                    const uint32_t seg1 = segs / 2;
+                    const uint32_t seg2 = segs - seg1;
+                    const uint32_t can_sjw = seg1 > 3 ? 3 : seg1;
+                    can_api_timing_cfg[0] = div;
+                    can_api_timing_cfg[1] = ((quanta - 1) & 0x3F) |
+                                            (can_sjw & 0x03) << 6 |
+                                            (seg1 & 0x0F) << 8 |
+                                            (seg2 & 0x07) << 12;
+                    return true;
+                }
+            }
+        }
+    }
+    return false;
+}
+
+bool canInit(uint32_t baudrate)
+{
+    static CCAN_CALLBACKS_T callbacks =
+    {
+        can_rx_callback,
+        can_tx_callback,
+        can_error_callback,
+        nullptr,
+        nullptr,
+        nullptr,
+        nullptr,
+        nullptr
+    };
+
+    Chip_Clock_EnablePeriphClock(SYSCTL_CLOCK_CAN);
+
+    static uint32_t can_api_init_table[2];
+    if (!calculateCanBaudrate(baudrate, can_api_init_table))
+    {
+        return false;
+    }
+
+    LPC_CCAN_API->init_can(can_api_init_table, true);
+    LPC_CCAN_API->config_calb(&callbacks);
+
+    NVIC_EnableIRQ(CAN_IRQn);
+    return true;
+}
+
+} // namespace
+
 int main()
 {
-    static long long zero_local;
+    if (!canInit(1000000))
+    {
+        while (1) { }
+    }
 
-    while (zero_global != 0) { } // BSS init check
-    while (zero_local != 0) { }
-    while (non_zero_global != 123456789123456789) { } // Data init check
-    while (post_initialized_global != 987654321987654321) { } // Constructor check
+    // Send a simple one time CAN message
+    msg_obj.msgobj = 0;
+    msg_obj.mode_id = 0x345;
+    msg_obj.mask = 0x0;
+    msg_obj.dlc = 4;
+    msg_obj.data[0] = 'T'; // 0x54
+    msg_obj.data[1] = 'E'; // 0x45
+    msg_obj.data[2] = 'S'; // 0x53
+    msg_obj.data[3] = 'T'; // 0x54
+    LPC_CCAN_API->can_transmit(&msg_obj);
+
+    // Configure message object 1 to receive all 11-bit messages 0x400-0x4FF
+    msg_obj.msgobj = 1;
+    msg_obj.mode_id = 0x400;
+    msg_obj.mask = 0x700;
+    LPC_CCAN_API->config_rxmsgobj(&msg_obj);
 
     while (true)
     {
         for (volatile int i = 0; i < 1000000; i++) { __asm volatile ("nop"); }
-        A a;
+        board::setStatusLed(true);
         for (volatile int i = 0; i < 1000000; i++) { __asm volatile ("nop"); }
+        board::setStatusLed(false);
     }
 }