16f877 portc.6 & portc.7

[DavyJones]

http://www.jonzilla.com/thebittners/...arm%20Project/

[skimask]

http://www.jonzilla.com/thebittners/...arm%20Project/

The board looks just fine to me, better than I've ever etched myself (see those earlier pic's?)
Only comment I've got about it is...those 90 degree angles... PCBs and 90 degree angles don't mix, especially if you've got any sort of high frequency running across the traces. Double 45 degree angles back to back with a small chunk of straight line at least twice as long as your trace is wide is MUCH better electrically than a single 90 degree corner. Why does it work? The short and simple answer is that the signal can't bounce back down the same path from which it came. Good enough for me and it's worked since I started doing it.

[BobK]

Since now one else caught it I will say it. Your TRISC = %0000000 should be TRISC=%00000000. That's 8 zeros for the 8 outputs. Your statement only had 7. I'm sure it was a minor detail but it had something to do with portC.7.

HTH,

BobK.

Yep no matter how careful you are with your pcb design, you always miss something. When I worked at a electronics place doing projects for the Navy we were not allowed to check our own work but when you are the only person working on your hobby project, it's kind of hard to have someone else check your work.

[mackrackit]

Since now one else caught it I will say it. Your TRISC = %0000000 should be TRISC=%00000000. That's 8 zeros for the 8 outputs. Your statement only had 7. I'm sure it was a minor detail but it had something to do with portC.7.

Darn bifocals

[DavyJones]

I got home this evening and soldered in the jumpers and woosh it worked like a charm. My led's are lighting up like the 4th.

Thanks for the advice on the 90's I'll certainly remember that with my next project. Not sure what that will be but this one certainly has been fun. Also good catch on my trisc statement I did not see that, I do wear bifocals just as an fyi. Got them around the time I turned 44.

This project has certainly been a learning experience and I'd have to say overall saved me a good sum of $$$ too. We put in a swimming pool last year and our local code said we had to have each door and each screen door have an alarm that sounds when you gain access to the pool area. I have 9 doors including the screens. The little gizmo's you can get at the pool store were $50 each that would have cost me $450 and they were unsightly. This controller and the the board I etched worked great and after installing the reed switches in the door with a friend one weekend I'm probably only into this for about $75.

Thanks everyone for your help. Not sure what I am going to work on next. I've got a second controller trying to think of something fun to make with it.

Cheers
David

[BobK]

Hi DavyJones,

I wear trifocals and each time I set a binary statement I go back and count the number of digits. Then I saw someone recently on the PBP forums doing this:

<pre> ' 76543210<br> TRISC= %00000000</pre>Seems to take the guesswork out of huh?

Glad you enjoyed your project! There's alot of valuable information on these forums and alot of great people helping each other out.


BobK

[paul borgmeier]

<pre> ' 76543210<br> TRISC= %00000000</pre>Seems to take the guesswork

you got to be careful but in this case

TRISC = %0

is exactly the same as

TRISC=%00000000

zero is still zero

glad you solved your problem