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miniblip USB piano example
Fork of Fruit_Piano by
main.cpp
- Committer:
- yihui
- Date:
- 2014-05-26
- Revision:
- 0:4755a81efb1d
- Child:
- 1:93bbcf91f356
File content as of revision 0:4755a81efb1d:
#include "mbed.h" #include "USBKeyboard.h" #define LOG(args...) // printf(args) #define THRESHOLD 2 #define TOUCH_N 6 BusOut leds(LED1, LED2, LED3, LED4); Ticker tick; USBKeyboard keyboard; uint8_t key_map[TOUCH_N] = {RIGHT_ARROW, LEFT_ARROW, DOWN_ARROW, UP_ARROW, ' ', '\n'}; PinName touch_pin[TOUCH_N] = {A0, A1, A2, A3, A4, A5}; DigitalInOut *p_touch_io[TOUCH_N]; uint8_t touch_data[TOUCH_N] = {0, }; void detect(void) { for (int i = 0; i < TOUCH_N; i++) { uint8_t count = 0; DigitalInOut *touch_io = p_touch_io[i]; touch_io->input(); touch_data[i] <<= 1; while (touch_io->read()) { count++; if (count > THRESHOLD) { touch_data[i] |= 0x01; break; } } touch_io->output(); touch_io->write(1); if (0x01 == touch_data[i]) { // a measurement is about the threshold, get a touch leds = 1 << i; keyboard.putc(key_map[i]); LOG("No %d key is touched\r\n", i); } else if (0x80 == touch_data[i]) { // last 7 measurement is under the threshold, touch is released leds = 0x00; LOG("No %d key is released\r\n", i); } } } int main() { // setup for (int i = 0; i < TOUCH_N; i++) { p_touch_io[i] = new DigitalInOut(touch_pin[i]); p_touch_io[i]->mode(PullDown); p_touch_io[i]->output(); p_touch_io[i]->write(1); } tick.attach(detect, 1.0 / 64.0); while(1) { // do something wait(1); } }