DEBUGG ISR LOOP : MUTEX GUARD PROTECTION LOCK USE SEMAPHORE FOR CALLING PROTECTED FUNCTIONS FROM ISR() BASIC OF SEMAPHORE FUNCTIONS /CREATION /& USE JAYDEEP SHAH - radhey04ec@gmail.com
main.cpp@0:090c812cb33b, 2020-07-12 (annotated)
- Committer:
- radhey04ec
- Date:
- Sun Jul 12 06:35:41 2020 +0000
- Revision:
- 0:090c812cb33b
PRINTF() WITH ISR ; SEMAPHORE BASIC USAGE; HOW HANDLE MUTEX GUARD FUNCTION WHEN call from ISR ??; ; JAYDEEP SHAH; radhey04ec@gmail.com;
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
radhey04ec | 0:090c812cb33b | 1 | //USE OF PRINTF() STATEMENT IN MBED WITH ISR |
radhey04ec | 0:090c812cb33b | 2 | |
radhey04ec | 0:090c812cb33b | 3 | //method : semaphore |
radhey04ec | 0:090c812cb33b | 4 | |
radhey04ec | 0:090c812cb33b | 5 | /* NOTE : PRINTF() IS PART OF STDIO.H LIBRARY |
radhey04ec | 0:090c812cb33b | 6 | AND THIS LIBRARY PROTECTED BY MUTEX GUARD, SO YOU CAN NOT CALL PRINTF() FROM |
radhey04ec | 0:090c812cb33b | 7 | ISR FUNCTION. |
radhey04ec | 0:090c812cb33b | 8 | SIMPLE WAY IS USE SOMETYPE OF SIGNAL OR FLAG AND PRINTF() OUTSIDE ISR depends on |
radhey04ec | 0:090c812cb33b | 9 | flag and signal */ |
radhey04ec | 0:090c812cb33b | 10 | |
radhey04ec | 0:090c812cb33b | 11 | //USE SERIAL TERMINAL WITH 9600 BAUD RATE 8-N-1 FORMAT |
radhey04ec | 0:090c812cb33b | 12 | |
radhey04ec | 0:090c812cb33b | 13 | //Created by : JAYDEEP SHAH --radhey04ec@gmail.com |
radhey04ec | 0:090c812cb33b | 14 | |
radhey04ec | 0:090c812cb33b | 15 | |
radhey04ec | 0:090c812cb33b | 16 | //Library Added ::::: |
radhey04ec | 0:090c812cb33b | 17 | #include "mbed.h" |
radhey04ec | 0:090c812cb33b | 18 | |
radhey04ec | 0:090c812cb33b | 19 | DigitalOut led(LED1); // ON BOARD LED |
radhey04ec | 0:090c812cb33b | 20 | InterruptIn btn(USER_BUTTON); // ON BOARD BUTTON PORT PC_13 |
radhey04ec | 0:090c812cb33b | 21 | //INTERRUPT REGISTERATION |
radhey04ec | 0:090c812cb33b | 22 | |
radhey04ec | 0:090c812cb33b | 23 | Semaphore updates(0); //SEMAPHORE OBJECT CREATE = SHARE RESOURCE 0 |
radhey04ec | 0:090c812cb33b | 24 | //NO SHARE RESOURCE ONLY ISR |
radhey04ec | 0:090c812cb33b | 25 | |
radhey04ec | 0:090c812cb33b | 26 | void do_something() { //ISR FUNCTION |
radhey04ec | 0:090c812cb33b | 27 | // release the semaphore |
radhey04ec | 0:090c812cb33b | 28 | updates.release(); // NOW V=1 |
radhey04ec | 0:090c812cb33b | 29 | } |
radhey04ec | 0:090c812cb33b | 30 | |
radhey04ec | 0:090c812cb33b | 31 | int main() { |
radhey04ec | 0:090c812cb33b | 32 | btn.fall(&do_something); |
radhey04ec | 0:090c812cb33b | 33 | |
radhey04ec | 0:090c812cb33b | 34 | while (1) { |
radhey04ec | 0:090c812cb33b | 35 | // wait for the semaphore to be released from the ISR |
radhey04ec | 0:090c812cb33b | 36 | uint32_t v = updates.wait(); //RETURN STORE IN V |
radhey04ec | 0:090c812cb33b | 37 | |
radhey04ec | 0:090c812cb33b | 38 | // now this runs on the main thread, and is safe |
radhey04ec | 0:090c812cb33b | 39 | if(v == 1) |
radhey04ec | 0:090c812cb33b | 40 | |
radhey04ec | 0:090c812cb33b | 41 | { |
radhey04ec | 0:090c812cb33b | 42 | led = !led; //LED TOGGLE |
radhey04ec | 0:090c812cb33b | 43 | printf("Toggle LED!\r\n"); //SERIAL PRINT |
radhey04ec | 0:090c812cb33b | 44 | } |
radhey04ec | 0:090c812cb33b | 45 | } |
radhey04ec | 0:090c812cb33b | 46 | } |