Pulsin Stabilization

[mackrackit]

An open pin is not a problem as long as you code it as an output near the beginning of the program.

You might try a debounce type of routine to hide false signals.

[Charles Linquis]

It might be helpful to take your unused GPIO.2 and connect it to the Rx of a RS-232 port on your PC, then use DEBUGOUT or SEROUT2 to send the value of PULSIN to the PC. It is even better if you have one of those little TTL-RS232 converters lying around and use that.

Serial ports make wonderful debugging tools.

[mister_e]

Motion seconded.

[Bobbo_ZA]

I actually have a Max232N board hanging around that i made up some time back and never used, will have a look at the DS again and see how to connect it again, :-) see if it can give me abything usefull.

So strange that the same / similar circuit can work in one application and then slightly modified it gives unstable results.

I suspect there may be something in my soldering but I went over it with a fine tooth comb and still its doing it, :-(

was tempted to dump it and remake it from scratch last night and start with the Rx input and single outout and then add the rest to it if it worked.

Question, Is it wise / required to run the Rx singnal through a resistor or should i connect it straight to the pin? Aslo, is there anything else i should do to the pin? i.e. res to Vcc or pullups etc?

[Bobbo_ZA]

Well, so i plugged the 12f onto the breadboard that has a 18f connected to a LCD and programed the 18F to show me what pulsin was giving me, the pulsin value ranges between around 120 and 180 which is what i expected, however, it only fluctuates by 4-5 points, in the code (above) I'm aksing it when the value is greater than 160 turn on the lighs and less than 130 turn them off, even when the pulsin is staying less than 130 or above 160 the lights randomly flash, :-(, pulling my hair out with this.

Replaced the PIC, rechecked all the connections and that all the respective tracks were cut on the vero etc yet it keeps doing it.

I tried averaging 3-4 readings but it still does it (causes my "strobe" LED to slow down quite a bit as well).

Considering scrapping it completly and starting from scratch, even replaced the cap (1uf...should i be using .1uf?) on vcc.

Many thanks
Rob

[Bobbo_ZA]

Just bought a Pickit 2, reckon my dodgy homebrew programmer might be a part of the issue, think i've been through 10 PICs in the last 2 hours keeps bombing the OSCAL value and toasting them, :-(

[Bobbo_ZA]

Damm, been busy this afternoon with the Pickit 2 and seems i still get the same issues, at least now i'm not killing Pics at a serious rate, even managed to recover some the winpic wouldnt read anymore.

Built a onboard glow this afternoon and its working 100%, the only difference between this issue and the onboard glow is that this one does not read / store the switch value, I'm working with hard coded values, :-(

[Bobbo_ZA]

Question, would powering the pic from a LM7805 (5v reg - giving 5.01v on the DMM) make a difference? all the others I power from the Rx, this one i've decided to use an external battery regulated down, still using a cap on vdd and gnd.