Programming Embedded Systems in C and C++

126 Chapter 9: Putting It All Together

/*********************************************************************

*

* Function: main()

*

* Description: This function is responsible for starting the ADEOS

* scheduler only.

*

* Notes:

*

* Returns: This function will never return!

*

*********************************************************************/

void

main(void)

{

os.start();

// This point will never be reached.

} /* main() */

Flashing the LED

As I said earlier, one of two things this application does is blink the red LED. This

is done by the code shown below. Here the function flashRed is executed as a

task. However, ignoring that and the new function name, this is almost exactly the

same Blinking LED function we studied in Chapter 7, Peripherals. The only differ-

ences at this level are the new frequency (10 Hz) and LED color (red).

#include "led.h"

#include "timer.h"

/**********************************************************************

*

* Function: flashRed()

*

* Description: Blink the red LED ten times a second.

*

* Notes: This outer loop is hardware-independent. However, it

* calls the hardware-dependent function toggleLed().

*

* Returns: This routine contains an infinite loop.

*

**********************************************************************/

void

flashRed(void)

{

Timer timer;

timer.start(50, Periodic); // Start a periodic 50 ms timer.

Flashing the LED 127

while (1)

{

toggleLed(LED_RED); ...