Timer

Gentlemen:

The use of the TIMER is for information only; it does NOT
control how the system operates.

The way my external circuit is set up, I use an external counter to total the number of cycles run, or to count the number of pulses output: if I ask for 10000 cycles with 1 pulse per cycle, the # cycles are EXACTLY 10000 cycles, but the number of output # pulses runs 10015 pulses. As the circuit is set up, if no new parallel port data is presented during a 1 millisec period, the previous data is repeated. Hence for the 10000 cycles, 15 input pulses NOT received or NOT recognized resulting in 15 repeats of the data preceeding the miss.

I am convinced that somehow, something is preventing the reception of an input pulse 1 1/2 times each second.

I see two alternatives to my dilemma:

1) Use the internal timer (Timer 0 or Timer 1) reset to divide the 1.19318 MHz clock to provide 1.164 KHz (divide by 1024) and use this for my circuit. (I have done this with Timer 0 and it works OK, but screws up the Time data). Use the 1.19318 MHz instead of my 1.0 MHz and run my present circuit off an ISA plug-in board. Hopefully this would provide a continuous uninterrupted train of pulses.

2) Arrange to use a hardware interrupt (on an ISA board) to receive my 1 KHz externally generated clock. Problem is, I have never done such an operation and have no experience re-doing interrupts. I would welcome assistance here!

Regards,
Jack C.