Pulse Narrower

[matth]

I need to input a 1PPS 100ms long positive pulse and output an approximate 130 microsecond negative pulse in sync with it. I am just modifying the incoming pulse to be narrower. Is there a simple way to do this without timers?

Matthew

[mister_e]

what else the PIC do??? Should the input pulse lenght be measure ???

[matth]

The pulse is coming from a GPS unit hopefully precision at 1PPS with a width on a 100ms. I just need to narrow the pulse to approximately 130 microseconds. The start points of both pulses need to be the same or very close.

Matthew

[mister_e]

i'm not 100% sure of the purpose of this but, is this input pulse will also be used for something else too??? if not why not just using an RC circuit with a voltage comparator, op-amp, FET, MOSFET or else to do the job? OR an OLD NE555 as monostable??


Also you can use interrupt to generate your pulse with PAUSEUS or PULSOUT. Depending of what else the PIC is doing, it could work really well.

It's possible that i don't understand... if so, just tell me.

[matth]

>>>if not why not just using an RC circuit with a voltage comparator, op-amp, FET, MOSFET or else to do the job? OR an OLD NE555 as monostable??

You are right any of those would likely work. Just thought Picbasic might be easier. Any good references on doing something like this with a 555?

Need to get my old tech school books out.

Matt