ep9312.c

IAR 开发环境的Cirrus Logic的例程

/*
 * $Revision: 1.3.26.1 $
 */
 
#include <intrinsics.h>
#include <ioep9312.h>

#define TC3OI_bit (1 << VIC2_TC3OI)

static void (*timer_function)();


//
// Interrupt handlers.
//

void TimerInterrupt()
{
  (*timer_function)(); // Call timer callback function.

  Timer3Clear = 0x0; // Clear timer 3 interrupt line.
}

// IRQ interrupt handler.
// Only the timer interrupt is used by this example.
__irq __arm void irq_handler(void)
{
  void (*interrupt_function)();
  unsigned int vector;

  // Called at 1000 Hz rate.
  vector = VIC2VectAddr; // Get interrupt vector.
  interrupt_function = (void(*)())vector;
  (*interrupt_function)(); // Call vectored interrupt function.

  VIC2VectAddr = 0; // Clear interrupt in VIC.
}


//
// Interrupt functions.
//

void EP9312InitInterrupt(void(*timer_func)())
{
  // Setup timer callback function.
  timer_function = timer_func;

  // Setup interrupt controller.
  VIC1Protection = 0;
  VIC2Protection = 0;
  // Disable all interrupts
  VIC1IntEnClear = 0xffffffff;
  VIC2IntEnClear = 0xffffffff;

  VIC2IntSelect &= ~TC3OI_bit; // IRQ on timer 3 line.
  VIC2VectAddr0 = (unsigned int)&TimerInterrupt;
  VIC2VectCntl0 = 0x20 | VIC2_TC3OI; // Enable vector interrupt for timer 3.
  VIC2IntEnable |= TC3OI_bit; // Enable timer 3 interrupt.
}


//
// Timer functions.
//

void EP9312InitTimer()
{
  Timer3Load = 508; // Set interrupt rate to 1000 Hz.
}

void EP9312StartTimer()
{
  Timer3Control = 0xc8; // Enable timer 3, periodic mode, 508 kHz clock.
}


//
// Parallel I/O functions.
//

void EP9312InitPIO()
{
  // Rely on setup done by boot program.
}


//
// LED output drivers.
//

void EP9312LedSet(unsigned int value)
{
  PEDR &= ~3; // Turn off both LED's.
  PEDR |= (value & 3); // Set LED's.
}