Content originally posted in LPCWare by groufosse on Tue Jun 04 15:46:58 MST 2013
Hi,
I have 2 different signals connected to 2 different pins: p1.26 (CAP0[0]) and p1.27 (CAP0[1])
Is it not possible to simultaneously receive signals on both of these pins? Since they are 2 unique registers, but on the same interrupt timer (TIMER0) I thought this was possible.
One of the inputs (CAP0[1]) is receiving pulses to be counted almost continuously. However, the other register (CAP0[1]) occasionally gets a block of pulses that also must be handled.
Here's sample code:
/TIMER0 interrupt handler sub-routine
void TIMER0_IRQHandler(void)
{
//assign Timer 0's interrupt register current value to test variable
interruptRegister = LPC_TIM0->IR;
if( interruptRegister & ( 1 << TIM_CR1_INT ) )
{
//or alternately, clear by setting the bit this way
LPC_TIM0->IR = ( 1 << TIM_CR1_INT );
motorTurnCtr++;
}
if( interruptRegister & ( 1 << TIM_CR0_INT ) )
{
//it's the communications interrupt.
LPC_TIM0->IR = ( 1 << TIM_CR0_INT );
//do some stuff.......
}
The above code causes the program to crash if the CR0 handler is quite busy. These are very low frequency signals, both < 500Hz. Wow, if the chip can't handle 2 inputs of this type of signal simultaneously, this is a real problem...
Any ideas, suggestions or glaring errors?
Thanks!
