@@ 45,6 45,8 @@ 
       <file file_name="targets/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/numeric_utils.h" />
       <file file_name="targets/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_tc.c" />
       <file file_name="targets/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_tc.h" />
+      <file file_name="targets/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_adc.c" />
+      <file file_name="targets/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_adc.h" />
     </folder>
   </project>
 </solution>

          

@@ 147,26 147,40 @@ ctl_board_init(void)
   d21_spi_set_pin_config(adafruit_m0_spis, ADAFRUIT_M0_SPI_AMOUNT);
   d2x_eic_init();
 
-  d21_configure_i2c1_bus();
+  // SCL & SDA pins on the Feather board.
+  d21_configure_i2c_bus(3, 100000);
 
+  // Polled uart0, pins 0 (RX) and 1 (TX) on Feather M0
   uart = d21_uart(0);
-
   ctl_uart_init(uart, NULL, NULL);
   ctl_uart_set_baud(uart, 9600);
   ctl_uart_puts(uart, "board initialized\r\n");
 
-  gpio_set_output(D2X_PORT_A, 17); // LED
+  gpio_set_output(LED_PORT, LED_PIN); // LED
 }
 
+static void button_press(uint8_t int_no, void *user_data)
+{
+  (void)int_no;
+  CTL_ISR_FN_t isr = (CTL_ISR_FN_t)user_data;
+  isr();
+}
+
+/* Adafruit Feather M0 Basic does not have buttons, but
+ * Oled wing has buttons A, B, and C. Button C is connected
+ * to pin D5 (PA15/EXTINT15).
+ */
 void
 ctl_board_on_button_pressed(CTL_ISR_FN_t isr)
 {
+  gpio_set_extint(SAMD_PORT(ARDUINO_D5), SAMD_PIN(ARDUINO_D5), false);
+  d2x_eic_enable_int(15, false, SENSE_EDGE_FALLING, button_press, isr);
 }
 
 void
 ctl_board_set_leds(unsigned v)
 {
-  gpio_set_state(D2X_PORT_A, 17, v != 0);
+  gpio_set_state(LED_PORT, LED_PIN, v != 0);
 }
 
 unsigned long

          
@@ 175,7 189,7 @@ platform_cpu_tick(void)
   return ctl_get_current_time();
 }
 
-
+/* Note, these spin delays are not accurate */
 void
 platform_spin_delay_cycles(unsigned long cycles)
 {

          

@@ 29,25 29,24 @@ 
 #include "libdevice/ctl_uart.h"
 #include "platform_atmel_d21_uart.h"
 
-CTL_TASK_t main_task, new_task;
+CTL_TASK_t main_task, led_task;
 
-#define CALLSTACKSIZE 16 // this is only required for AVR builds
 #define STACKSIZE 64          
-unsigned new_task_stack[1+STACKSIZE+1];
+unsigned led_task_stack[1+STACKSIZE+1];
 
 void 
-new_task_code(void *p)
+led_task_code(void *p)
 {  
   unsigned int v=0;
   CTL_UART_t *uart = d21_uart(0);
 
-  ctl_uart_puts(uart, "new_task_code started\r\n");
+  ctl_uart_puts(uart, "led_task_code started\r\n");
   while (1)
     {      
       // task logic goes here      
       v++;
       ctl_board_set_leds(v % 2);
-      ctl_timeout_wait(ctl_get_current_time() + ctl_get_ticks_per_second()*10);
+      ctl_timeout_wait(ctl_get_current_time() + ctl_get_ticks_per_second() * 3);
     }  
 }
 

          
@@ 66,14 65,14 @@ int main(void)
   ctl_board_init();
   ctl_board_set_leds(1);
 
-  memset(new_task_stack, 0xcd, sizeof(new_task_stack));  // write known values into the stack
-  new_task_stack[0]=new_task_stack[1+STACKSIZE]=0xfacefeed; // put marker values at the words before/after the stack
-  ctl_task_run(&new_task, 1, new_task_code, 0, "new_task", STACKSIZE, new_task_stack+1, CALLSTACKSIZE);
+  memset(led_task_stack, 0xcd, sizeof(led_task_stack));  // write known values into the stack
+  led_task_stack[0]=led_task_stack[1+STACKSIZE]=0xfacefeed; // put marker values at the words before/after the stack
+  ctl_task_run(&led_task, 1, led_task_code, 0, "led_task", STACKSIZE, led_task_stack+1, 0);
   ctl_task_set_priority(&main_task, 0); // drop to lowest priority to start created tasks running.
   while (1)
     {    
-      // power down can go here if supported      
-      v++;
+      // tickless idle mode
+      ctl_sleep(ctl_get_sleep_delay());
     }
   return 0;
 }

          

@@ 189,6 189,8 @@ 
       <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_gpio.c" expand="no"/>
       <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_eic.h" expand="no"/>
       <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_eic.c" expand="no"/>
+      <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_adc.h" expand="no"/>
+      <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_adc.c" expand="no"/>
       <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_rtc.h" expand="no"/>
       <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_rtc.c" expand="no"/>
       <file name="$(TargetsDir)/Adafruit_Feather_M0_Basic/samd2x-peripheral-lib/d2x_tc.c" expand="no"/>