Ted Lin
implement button press/release with double check using coroutine
Revision 0:54509830df20, committed 2016-08-28
- Comitter:
- mintisan
- Date:
- Sun Aug 28 12:50:45 2016 +0000
- Commit message:
- implement button press/release with double check using coroutine
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/coroutine.h Sun Aug 28 12:50:45 2016 +0000
@@ -0,0 +1,34 @@
+#ifndef COROUTINE_H_
+#define COROUTINE_H_
+
+#ifdef __cplushplus
+extern "C"{
+#endif
+
+/**
+ * C coroutine
+ * https://github.com/mintisan/mintisan.github.io/wiki/C#coroutine
+ */
+
+#define cr_start() \
+ static int __s = 0; \
+ switch(__s){ \
+ case 0:
+
+// '\' doesn't count for one line in C
+#define cr_yield(condition) do{ \
+ __s = __LINE__ ; \
+ case __LINE__: \
+ if(condition) \
+ return; \
+ }while(0)
+
+#define cr_end() \
+ } __s = 0;
+
+
+#ifdef __cplushplus
+}
+#endif
+
+#endif
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Sun Aug 28 12:50:45 2016 +0000
@@ -0,0 +1,111 @@
+#include "mbed.h"
+#include "coroutine.h"
+//------------------------------------
+// USER_KEY-PB_3 / USER_BUTTON-PC_13
+//------------------------------------
+DigitalIn mybutton(PB_3);
+//------------------------------------
+// LED1-PA5
+//------------------------------------
+DigitalOut myled(PA_5);
+//------------------------------------
+// Hyperterminal configuration
+// 9600 bauds, 8-bit data, no parity
+// SERIAL_TX-PA2, SERIAL_RX-PA3
+//------------------------------------
+Serial pc(PA_2, PA_3);
+
+Ticker jitter;
+
+#define entry() pc.printf("func:%s\n", __FUNCTION__)
+
+#define error() pc.printf("Error! func:%s, line: %d\n", __FUNCTION__, __LINE__)
+
+enum{OFF=0,ON=1};
+enum{PRESS= 0, RELEASE = 1, UNKNOWN};
+#define PRESS_JITTER_TIME 0.01 // 10ms
+#define RELEASE_JITTER_TIME 0.02 // 20ms
+uint8_t cur_flag_status = UNKNOWN;
+uint8_t pre_flag_status = UNKNOWN;
+
+volatile uint16_t cr_time_down;
+volatile uint16_t cr_time_up;
+
+void isr_ticker() {
+ cr_time_down++;
+ cr_time_up++;
+}
+
+
+void update_key_status(void)
+{
+ pre_flag_status = cur_flag_status;
+ cur_flag_status = mybutton.read();
+}
+
+void key_down_status(void)
+{
+ update_key_status();
+ if(cur_flag_status == PRESS){
+ if(myled.read()!=ON){
+ if(pre_flag_status == PRESS){
+ myled = ON;
+ pc.printf("Pressed\n");
+ }
+ }
+ }
+}
+
+void key_up_status(void)
+{
+ update_key_status();
+ if(cur_flag_status == RELEASE){
+ if(myled.read()!=OFF){
+ if(pre_flag_status == RELEASE){
+ myled = OFF;
+ pc.printf("Released\n");
+ }
+ }
+ }
+}
+
+void user_thread_down(void)
+{
+ cr_start();
+
+ // inital once each loop
+ cr_time_down = 0;
+ // waiting for condition is satisfied, or will be yield
+ cr_yield(cr_time_down != 1);
+ key_down_status();
+
+ cr_end();
+}
+
+void user_thread_up(void)
+{
+ cr_start();
+
+ // inital once each loop
+ cr_time_up = 0;
+ // waiting for condition is satisfied, or will be yield
+ cr_yield(cr_time_up != 2);
+ key_up_status();
+
+ cr_end();
+}
+
+/*
+ * one coroutine for down check;
+ * another coroutine for up check.
+ */
+int main(void)
+{
+ myled = OFF;
+ jitter.attach(&isr_ticker, PRESS_JITTER_TIME);
+ while(1) {
+ user_thread_down();
+ user_thread_up();
+ // extend more task here
+ }
+}
\ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-dev.lib Sun Aug 28 12:50:45 2016 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed-dev/#423e1876dc07