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Sam
- 13th September 2009, 01:37
I have been searching Microchip.com and haven't found any 8 pin DIP PIC's with 6 output. The MCLR is always an input only, which I basically understand but is there any model with 6 outputs.

Thanks,

Steve

mackrackit
- 13th September 2009, 01:52
As far as I know you will always have Vdd, VSS and MCLR.

What are you trying to do? Maybe there is another solution?

Sam
- 13th September 2009, 02:10
The simple answer to that is, control 6 LED's separately with only a 8 pin DIP package.

dhouston
- 13th September 2009, 02:57
http://ww1.microchip.com/downloads/en/devicedoc/40040b.pdf

And with one input to spare.

Sam
- 13th September 2009, 03:06
I have been searching Microchip.com and haven't found any 8 pin DIP PIC's with 6 output. The MCLR is always an input only, which I basically understand but is there any model with 6 outputs.

Thanks,

Steve


http://ww1.microchip.com/downloads/en/devicedoc/40040b.pdf

And with one output to spare.

Hi Dave,

I figure (?) you're talking about tip 2 I/O multiplexing ? That may just work for my application. I'll take a close look at it now, it however means redesigning my PCB and changing the code.

And wouldn't it leave 2 outputs to spare, GPIO.4 and .5 ?

Thanks,

SS

EDIT: or was it tip 3 ?

mackrackit
- 13th September 2009, 03:50
Here is another option.
http://www.picbasic.co.uk/forum/showthread.php?t=10200
But it would be a complete redesign.

Sam
- 13th September 2009, 04:24
Here is another option.
http://www.picbasic.co.uk/forum/showthread.php?t=10200
But it would be a complete redesign.

Well that's very impressive that your 7 year old did some of the the work and the code ! And it's a very nice project, but it's not practical for my project as it must be on a 1" diameter single sided PCB.

Thanks for the link anyway, it looks like the multiplexing will have to be the way to go for me.

SS

dhouston
- 13th September 2009, 13:33
I figure (?) you're talking about tip 2 I/O multiplexing ? That may just work for my application. I'll take a close look at it now, it however means redesigning my PCB and changing the code.

And wouldn't it leave 2 outputs to spare, GPIO.4 and .5 ?Yes, I meant Tip 2. It was past my bedtime - I meant to say it would leave an input pn free plus two input/output pins.

Sam
- 13th September 2009, 18:14
Hey Dave,

Thank you very much, that multiplexing completely solved my issue ! I never thought about doing it like that but once you see it (tip 2) it makes perfect sense. It's just what I needed and it's working great.

You're a great asset to the forum and I really appreciate all your help,

SS

dhouston
- 13th September 2009, 18:37
I'm surprised I remembered it. I had a copy of that PDF on a network HDD which failed a few weeks back but vaguely recalled it had several unconventional but simple methods for getting the most out of minimal hardware. I have a new, bigger NAS drive but had not grabbed a copy of the PDF until your post jogged my synapses.

The Atmel AVR ATTiny12 allows you to use MCLR as an open drain output but its pinout is different.

falingtrea
- 14th September 2009, 18:38
I think that is officially called "Charlieplexing" and is a method originally though up by someone from Maxim Semi. Check this webpage:

http://en.wikipedia.org/wiki/Charlieplexing

Acetronics2
- 14th September 2009, 19:25
Hi,

This is not exactly PBP **smiles** , but this could help ... looks like PBP !

Alain

Melanie
- 14th September 2009, 20:15
If you wanted a PBP example...

http://www.picbasic.co.uk/forum/showthread.php?t=3510&highlight=Electronic+Dice