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#include "mbed.h"
#include "spi_init.h"
#include "counter.h"
#include "Adafruit_SSD1306.h"
#define SW_PINS p22, p23, p24, p25
#define SW_PERIOD 20000 // 20ms
void tout(void);
// Onboard LED
DigitalOut alive(LED1);
PinName switch_pin[] = { SW_PINS };
Counter *switch_position[4];
Ticker timer;
volatile uint16_t switch_count[4] = { 0, 0, 0, 0 };
volatile uint16_t update = 0;
// Initialise display
SPInit gSpi(D_MOSI_PIN, NC, D_CLK_PIN);
Adafruit_SSD1306_Spi oled(gSpi, D_DC_PIN, D_RST_PIN, D_CS_PIN, 64, 128);
int main(void)
{
// Enable ISR for the switch rising edge
for (int i = 0; i < 3; ++i) {
switch_position[i] = new Counter(switch_pin[i]);
}
//Attach switch sampling timer ISR to the timer instance with the required period
timer.attach_us(&tout, SW_PERIOD);
oled.setRotation(2);
oled.printf("%ux%u OLED Display\r\n", oled.width(), oled.height());
for (;;) {
if (update) {
update = 0;
oled.setTextCursor(0, 0);
//Write the latest switch osciallor count
for (int i = 0; i < 3; ++i) {
oled.printf("\n%05u ", switch_count[i]);
}
//Copy the display buffer to the display
oled.display();
alive = !alive;
}
}
}
//Interrupt Service Routine for the switch sampling timer
void tout(void)
{
// Query how many times switch triggered
for (int i = 0; i < 3; ++i) {
switch_count[i] = switch_position[i]->read();
switch_position[i]->write(0);
}
// Update display
update = 1;
}
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