Initial CAN support for LM3S.

src/platform/lm3s/conf.py

@@ -1,5 +1,5 @@
 # Configuration file for the LM3S microcontroller
-specific_files = "startup_gcc.c platform.c uart.c sysctl.c gpio.c ssi.c timer.c pwm.c ethernet.c systick.c flash.c interrupt.c cpu.c adc.c"
+specific_files = "startup_gcc.c platform.c uart.c sysctl.c gpio.c ssi.c timer.c pwm.c ethernet.c systick.c flash.c interrupt.c cpu.c adc.c can.c"
 
 if comp[ 'board' ] == 'EK-LM3S1968' or comp[ 'board' ] == 'EK-LM3S6965' or comp[ 'board' ] == 'EK-LM3S8962':
   specific_files = specific_files + " rit128x96x4.c disp.c"

src/platform/lm3s/platform.c

@@ -28,9 +28,11 @@
 #include "hw_types.h"
 #include "hw_pwm.h"
 #include "hw_nvic.h"
+#include "hw_can.h"
 #include "hw_ethernet.h"
 #include "debug.h"
 #include "gpio.h"
+#include "can.h"
 #include "interrupt.h"
 #include "sysctl.h"
 #include "uart.h"
@@ -82,6 +84,7 @@ static void pios_init();
 static void pwms_init();
 static void eth_init();
 static void adcs_init();
+static void cans_init();
 
 int platform_init()
 {
@@ -112,6 +115,11 @@ int platform_init()
   adcs_init();
 #endif
 
+#ifdef BUILD_CAN
+  // Setup CANs
+  cans_init();
+#endif
+
   // Setup ethernet (TCP/IP)
   eth_init();
 
@@ -214,6 +222,97 @@ pio_type platform_pio_op( unsigned port, pio_type pinmask, int op )
   return retval;
 }
 
+
+// ****************************************************************************
+// CAN
+
+volatile u32 can_rx_flag = 0;
+volatile u32 can_err_flag = 0;
+char can_tx_buf[8];
+tCANMsgObject can_msg_rx;
+
+void CANIntHandler(void)
+{
+  u32 status = CANIntStatus(CAN0_BASE, CAN_INT_STS_CAUSE);
+
+  if(status == CAN_INT_INTID_STATUS)
+  {
+    status = CANStatusGet(CAN0_BASE, CAN_STS_CONTROL);
+    can_err_flag = 1;
+  }
+
+  else if( status == 1 )
+  {
+    CANIntClear(CAN0_BASE, 1);
+    can_rx_flag = 1;
+    can_err_flag = 0;
+  }
+}
+
+
+void cans_init( void )
+{
+  GPIOPinConfigure(GPIO_PD0_CAN0RX);
+  GPIOPinConfigure(GPIO_PD1_CAN0TX);
+  MAP_GPIOPinTypeCAN(GPIO_PORTD_BASE, GPIO_PIN_0 | GPIO_PIN_1);
+
+  MAP_SysCtlPeripheralEnable( SYSCTL_PERIPH_CAN0 ); 
+  MAP_CANInit( CAN0_BASE );
+  CANBitRateSet(CAN0_BASE, SysCtlClockGet(), 500000);
+  MAP_CANIntEnable( CAN0_BASE, CAN_INT_MASTER | CAN_INT_ERROR | CAN_INT_STATUS );
+  MAP_IntEnable(INT_CAN0);
+  MAP_CANEnable(CAN0_BASE);
+
+  // Configure default catch-all message object
+  can_msg_rx.ulMsgID = 0;
+  can_msg_rx.ulMsgIDMask = 0;
+  can_msg_rx.ulFlags = MSG_OBJ_RX_INT_ENABLE | MSG_OBJ_USE_ID_FILTER;
+  can_msg_rx.ulMsgLen = 8;
+  MAP_CANMessageSet(CAN0_BASE, 1, &can_msg_rx, MSG_OBJ_TYPE_RX);
+}
+
+
+u32 platform_can_setup( unsigned id, u32 clock )
+{  
+  MAP_CANDisable(CAN0_BASE);
+  CANBitRateSet(CAN0_BASE, SysCtlClockGet(), clock );
+  MAP_CANEnable(CAN0_BASE);
+}
+
+void platform_can_send( unsigned id, u32 canid, u8 idtype, u8 len, const u8 *data )
+{
+  tCANMsgObject msg_tx;
+  const char *s = ( char * )data;
+  char *d;
+  
+  if( idtype )
+    msg_tx.ulFlags |= MSG_OBJ_EXTENDED_ID;
+  
+  msg_tx.ulMsgIDMask = 0;
+  msg_tx.ulMsgID = canid;
+  msg_tx.ulMsgLen = len;
+  msg_tx.pucMsgData = d;
+
+  d = can_tx_buf;
+  DUFF_DEVICE_8( len,  *d++ = *s++ );
+  
+  CANMessageSet(CAN0_BASE, 2, &msg_tx, MSG_OBJ_TYPE_TX);
+}
+
+void platform_can_recv( unsigned id, u32 *canid, u8 *idtype, u8 *len, u8 *data )
+{
+  // wait for a message
+  while( can_rx_flag == 0 );
+
+  can_msg_rx.pucMsgData = data;
+  CANMessageGet(CAN0_BASE, 1, &can_msg_rx, 0);
+  can_rx_flag = 0;
+
+  *canid = ( u32 )can_msg_rx.ulMsgID;
+  *idtype = (can_msg_rx.ulFlags & MSG_OBJ_EXTENDED_ID)? 1 : 0;
+  *len = can_msg_rx.ulMsgLen;
+}
+
 // ****************************************************************************
 // SPI
 // Same configuration on LM3S8962, LM3S6965, LM3S6918 and LM3S9B92 (2 SPI ports)

src/platform/lm3s/platform_conf.h

@@ -45,6 +45,13 @@
 #define PS_LIB_TABLE_NAME   "lm3s"
 #endif
 
+#if defined( FORLM3S8962 ) || defined( FORLM3S9B92 )
+#define CANLINE  _ROM( AUXLIB_CAN, luaopen_can, can_map )
+#define BUILD_CAN
+#else
+#define CANLINE
+#endif
+
 #ifdef FORLM3S6918
 #define PWMLINE
 #else
@@ -78,6 +85,8 @@
 #define PLATLINE
 #endif
 
+
+
 #define LUA_PLATFORM_LIBS_ROM\
   _ROM( AUXLIB_PIO, luaopen_pio, pio_map )\
   _ROM( AUXLIB_SPI, luaopen_spi, spi_map )\
@@ -93,6 +102,7 @@
   _ROM( AUXLIB_CPU, luaopen_cpu, cpu_map )\
   _ROM( AUXLIB_ELUA, luaopen_elua, elua_map )\
   ADCLINE\
+  CANLINE\
   RPCLINE\
   _ROM( LUA_MATHLIBNAME, luaopen_math, math_map )\
   PLATLINE
@@ -151,7 +161,7 @@
   #define NUM_PWM             0
 #endif  
 #define NUM_ADC               4
-#define NUM_CAN               0
+#define NUM_CAN               1
 
 // Enable RX buffering on UART
 //#define BUF_ENABLE_UART

src/platform/lm3s/startup_gcc.c

@@ -41,6 +41,7 @@ extern void EthernetIntHandler();
 extern void SysTickIntHandler();
 extern void ADCIntHandler();
 extern void UARTIntHandler();
+extern void CANIntHandler();
 
 #include "hw_memmap.h"
 #include "platform_conf.h"
@@ -128,7 +129,7 @@ void (* const g_pfnVectors[])(void) =
     IntDefaultHandler,                      // Timer 3 subtimer B
     IntDefaultHandler,                      // I2C1 Master and Slave
     IntDefaultHandler,                      // Quadrature Encoder 1
-    IntDefaultHandler,                      // CAN0
+    CANIntHandler,                          // CAN0
     IntDefaultHandler,                      // CAN1
     IntDefaultHandler,                      // CAN2
     EthernetIntHandler,                     // Ethernet