Quad encoder problems

[mister_e]

The encoders output a positive voltage between ~1.85 and 5 and I have 4.7K resistors pulled to ground on each channel.

So it's never 0V? @1.85 you're probably sometimes in-between Low and High logic Level. You may need to 'filter' it a little bit to avoid oddity.

1.Use the internal voltage comparator, set the threshold and use their interrupt to increment the counter.
OR
2.try something like...
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=1067&stc=1&d=115794620 6">
maybe one diode could be enough... maybe not
HTH

[smitty505000]

I got it working! Sort of. I played arround with different value resistors and some diodes as sugested by mister_e and ended up with 30K resistors. Also seams my pic16f628-20p dosnt have a very accurate osc in it. I hooked up an external resonator and it works at 20mhz using Steve's slightly modified code from post #12. Thanks Steve!
The only thing now is it sometimes skips or looses count. Either the pic running at 20mhz cant keep up or the infrared red rx cant keep up. These encoders came out of a PS2 computer mouse. The ones that turn off the ball.

Any ideas guys?

Thanks!
Smitty

[SteveB]

I got it working! Sort of. I played arround with different value resistors and some diodes as sugested by mister_e and ended up with 30K resistors. Also seams my pic16f628-20p dosnt have a very accurate osc in it. I hooked up an external resonator and it works at 20mhz using Steve's slightly modified code from post #12. Thanks Steve!
The only thing now is it sometimes skips or looses count. Either the pic running at 20mhz cant keep up or the infrared red rx cant keep up. These encoders came out of a PS2 computer mouse. The ones that turn off the ball.

Any ideas guys?

Thanks!
Smitty

Now your walking, time to RUN!! Go back to post #6 and give the interrupts a try. With the optical encoders and interrupts, you should have not any switch bounce, and you should also not have any "skips". Well, if it turns faster than the interrupts can process the inputs, you can have some skips, but the nice thing about the interrupts is that the updates to the rotarty encoders count will not "wait" on the LCD output to finish.

Give it a shot,
Steve

[smitty505000]

Steve,
I am ready to run but cant get it to compile. I am not sure what I am doing wrong. Did you get it to compile?

Thank you for all your help!

Smitty

[SteveB]

Yes, it compiles. You need to use Microchips Assembler instead of the MeLabs. What errors are you getting? (Are you using MicroCode Studio?)

[smitty505000]

Hey Steve,

I have tried microcode studio and microchips mpasm. I think I might have a problem with mpasm talking to pbp or I installed something wrong. I was going to unistall everything and try again but my pbp is on a floppy and I found out my floppy drive (havent used it in years! LOL) is bad. I ordered a new one and will have it by the end of the week. Its amazing how cheap a floppy drive is these days. I also ordered my first Oscilloscope! Its only a BK precision 2120b 30mhz dual channel but it should be able to handle everything I do.

Thanks,
Smitty

[SteveB]

I think others may have had the same problem. DynamoBen recently got his to work. Maybe he can help sort out whats wrong. He mentions that he "changed the registry", but no specifics. Not having had a problem with my setup, I'd just be guessing.

The other alternative is writing the interrupt routine is ASM. Better to get your compiler/assembler arrangement working properly.

Steve