more external interrupts?

Can i use PulseIn() as a sort of external interrupt?

Or is there a better way to set up more external interrupts?

I would like to monitor the time between pulses of at least 4 reed switches.

my program is working perfectly using one of the external interrupts currently.

Any ideas would be greatly appreciated.

Thanks Jeff O'Brien

You can use pin-change interrupts.

  • Ben

There are IO expander ICs that interface to the ATmega via SPI or I2C. Some of these have a single interrupt pin to drive the ATmega’s interrupt input - your ISR would need to poll the expander to find out what triggered the interrupt.