Yoshi Mimura
vehicle CAN message log to SD file system using ring buffer memory
Dependencies: SDFileSystem mbed
Revision 0:de9553dd79ec, committed 2013-01-25
- Comitter:
- ym1784
- Date:
- Fri Jan 25 21:04:19 2013 +0000
- Child:
- 1:4a538cae9042
- Commit message:
- initial version
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/SDFileSystem.lib Fri Jan 25 21:04:19 2013 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/SDFileSystem/#c8f66dc765d4
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Fri Jan 25 21:04:19 2013 +0000
@@ -0,0 +1,161 @@
+// CAN message log to SD card using can2.attach with ring buffer
+// 2013/Jan/25 using official SDFileSyatem library
+
+#include "mbed.h"
+#include "SDFileSystem.h"
+
+CAN can2(p30, p29);
+CANMessage can_MsgRx;
+Timer timer;
+
+// LED to know the status
+DigitalOut User_Led1(LED1);
+DigitalOut User_Led2(LED2);
+DigitalOut User_Led3(LED3);
+DigitalOut User_Led4(LED4);
+#define LED_ON 1
+#define LED_OFF 0
+
+// status monitor
+Serial pc(USBTX, USBRX);
+
+SDFileSystem sd(p5, p6, p7, p8, "sd"); // mosi, miso, sclk, cs, name
+FILE *fp;
+int file_open = 0;
+
+// button switch for closing file
+DigitalIn button1(p16);
+DigitalIn button2(p17);
+DigitalIn button3(p18);
+DigitalIn button4(p19);
+int SW0 = 0x0f, SW1 = 0x0f, SW2 = 0x0f, BUTTON = 0;
+Ticker sw_check;
+
+// function prototypes
+void can_check(void);
+void check_sw();
+
+// CAN message buffer
+#define BUFFER_SIZE 512 // buffer size must be power of 2
+#define BUFFER_MASK ( BUFFER_SIZE - 1 )
+unsigned int second[BUFFER_SIZE];
+unsigned short can_id[BUFFER_SIZE];
+unsigned char msg_length[BUFFER_SIZE];
+unsigned char data[8][BUFFER_SIZE];
+volatile unsigned int head = 0;
+volatile unsigned int tail = 0;
+
+int main()
+{
+ button1.mode(PullUp);
+ button2.mode(PullUp);
+ button3.mode(PullUp);
+ button4.mode(PullUp);
+ sw_check.attach_us(&check_sw, 5000); // status check every 5 msec
+
+ can2.frequency(500000);
+ pc.baud(9600);
+ pc.printf("CAN log to SD card using ring buffer, 9600 bps\r\n");
+
+ User_Led1 = LED_OFF;
+ User_Led2 = LED_OFF;
+ User_Led3 = LED_OFF;
+ User_Led4 = LED_OFF;
+
+ char file_name[20];
+
+ time_t t;
+ t = time( NULL ) + 32400; // UTC + 9 hours for JST
+ strftime( file_name, 20, "/sd/%y%m%d%H%M.log", localtime( &t ) );
+ pc.printf( "log file is %s\r\n", file_name );
+
+ fp = fopen(file_name, "w");
+ if ( fp == NULL ) {
+ pc.printf("Unable to create the file '%s'\r\n", file_name);
+ pc.printf("Please try again\r\n");
+
+ User_Led1 = LED_OFF;
+ file_open = 0;
+ } else {
+ User_Led1 = LED_ON;
+ file_open = 1;
+ }
+
+ timer.stop();
+ timer.reset();
+ timer.start();
+ can2.attach(&can_check);
+
+ int tmptail;
+ while(1) {
+ if ( head != tail ) {
+ tmptail = (tail + 1) & BUFFER_MASK;
+ fprintf(fp, "%03X,%03X,", head&0xfff, tmptail&0xfff);
+ fprintf(fp, "%08X,", second[tmptail]);
+ fprintf(fp, "t%03X%d", can_id[tmptail], msg_length[tmptail]);
+
+ for (int i=0; i<msg_length[tmptail]; i++) {
+ fprintf(fp, "%02X", data[i][tmptail]);
+ } // for
+ fprintf(fp, "\r\n");
+
+ tail = tmptail; // update tail after data sent
+ if ( tail == 0 ) {
+ // toggle led3
+ User_Led3 = !User_Led3;
+ t = time( NULL ) + 32400; // UTC + 9 hours for JST
+ strftime( file_name, 20, "%T", localtime( &t ) );
+ pc.printf("new cycle of ring buffer at %s\r\n", file_name);
+ }
+ } // if head != tail
+
+ if ( BUTTON&0x01 ) { // button1 pressed
+ BUTTON &= 0xfe; // clear button status
+ can2.attach(0); // detach CAN interrupt
+ file_open = 0;
+ //Close the file
+ fclose(fp);
+ pc.printf("file closed\r\n");
+ User_Led1 = LED_OFF;
+ } // if button
+ } // while
+} // main
+
+// read CAN2 message using intterupt and ring buffer
+void can_check(void) {
+ int temp_head;
+ if ( file_open == 1 ) {
+ while ( can2.read(can_MsgRx) ) {
+ temp_head = (head + 1) & BUFFER_MASK;
+ if ( temp_head == tail ) { // buffer overflow error
+ fclose(fp);
+ fprintf(stderr, "buffer overflow\r\n");
+ fprintf(stderr, "head = %d\r\n", head);
+ fprintf(stderr, "tail = %d\r\n", tail);
+ User_Led4 = 1;
+ exit(1);
+ } // if
+
+ second[temp_head] = timer.read_us();
+ can_id[temp_head] = can_MsgRx.id & 0xFFF;
+ msg_length[temp_head] = can_MsgRx.len;
+ for (int i=0; i<can_MsgRx.len; i++) {
+ data[i][temp_head] = can_MsgRx.data[i];
+ } // for
+ head = temp_head; // update head after data stored
+ // toggle led2
+ User_Led2 = !User_Led2;
+ } // while
+ } // if open
+} // can_check
+
+// read switch status, called every 5 msec
+void check_sw() {
+ SW2 = SW1; // shift previous status
+ SW1 = SW0; // shift previous status
+// get new status
+ SW0 = button1.read()+(button2.read()<<1)+(button3.read()<<2)+(button4.read()<<3);
+// following sequence detects switch press edge
+// HIGH(SW2) -> LOW(SW1) -> LOW(SW0)
+ BUTTON |= ((~(SW0|SW1))&SW2); // update button status
+} // check_sw
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Fri Jan 25 21:04:19 2013 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/0954ebd79f59 \ No newline at end of file