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wmmullaney · 28th November 2007, 08:15 PM

Hello again, i was looking at this pic PIC16F628, is there a compatible pic that has an internal oscillator? I was looking at this programmer, is the serial connection male or female?

(R1 is 2.2k)

wmmullaney · 28th November 2007, 08:40 PM

can I use 5k resistors?

**Nigel Goodwin** · 28th November 2007, 09:26 PM

Quote:

Originally Posted by wmmullaney

Hello again, i was looking at this pic PIC16F628, is there a compatible pic that has an internal oscillator?

The 16F628 has an internal oscillator, that's why I chose it for my tutorials, plus it was the replacement for the popular old 16F84.

wmmullaney · 28th November 2007, 10:07 PM

Ok, must have missed it in the data sheets, were can I find your tutorials?

5k Resistors?

wmmullaney · 29th November 2007, 01:21 AM

Found this.

http://www.jdm.homepage.dk/easypic.htm

Is "R" needed?

Gayan Soyza · 29th November 2007, 03:53 AM

Your programmer will give you trouble in a small variation on your comport voltages & in your supply.In your programmers it needs external 5V.If the voltage exactly 5V you don't need the resister.Most JDM type uses 5.1 zenners.

Try making the JDM programmer here is the simple version of that working well.
No need external supply.
http://www.semis.demon.co.uk/uJDM/uJDMmain.htm

**Nigel Goodwin** · 29th November 2007, 08:47 AM

Quote:

Originally Posted by wmmullaney

Ok, must have missed it in the data sheets, were can I find your tutorials?

In my signature at the bottom of all of my posts!.

Quote:

5k Resistors?

It's a crude nasty 'programmer', and they tend to give lots of problems, and only work on some computers.

wmmullaney · 29th November 2007, 06:51 PM

Ok, I'v seen the uJDM, kinda wanted something simpler just to start, after that I want to get a JDM programmer from Sparkfun.

So, 5k resistors will work.

I hope to have my projects up and running by Christmas.

**Nigel Goodwin** · 29th November 2007, 07:12 PM

Quote:

Originally Posted by wmmullaney

Ok, I'v seen the uJDM, kinda wanted something simpler just to start, after that I want to get a JDM programmer from Sparkfun.

The JDM is really too simple to be reliable, and is fussy about the particular machine it's connected to.

wmmullaney · 29th November 2007, 07:33 PM

What do you suggest? I don't have 50+ dollars to spend. Or to many parts to build one with.

wmmullaney · 29th November 2007, 07:35 PM

Is the PIC16F628 compatible with the PIC16f84?

matc · 29th November 2007, 08:30 PM

Define "compatible" ? It's not the same part, but check the datasheets for pinout compatibility.

**Nigel Goodwin** · 29th November 2007, 08:53 PM

Quote:

Originally Posted by wmmullaney

Is the PIC16F628 compatible with the PIC16f84?

It replaced it last century, the 84 has effectively been obselete for a LONG time now. The 628 is cheaper, higher spec, and pin compatible with the 84, requiring only extremely minor changes to the source code to run.

wmmullaney · 29th November 2007, 10:29 PM

I meant in a programmer.

wmmullaney · 29th November 2007, 10:36 PM

On the "simplest programmer in the world" what does he mean when he says vdd not to be pulled higher than .5v?

Quote:

Originally Posted by Jens Dyekjær Madsen

In fact, the clamp diodes to Vdd is not diodes, but transistors, and about 80% of the current flows into ground. Because of this, are Vdd not to be pulled higher than Vdd+0.5V, even all the inputs pulls high.

Does this mean R is needed? even if the 5v is regulated?

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28th November 2007, 08:40 PM	(permalink)
wmmullaney	can I use 5k resistors?

28th November 2007, 10:07 PM	(permalink)
wmmullaney	Ok, must have missed it in the data sheets, were can I find your tutorials? 5k Resistors?

29th November 2007, 01:21 AM	(permalink)
wmmullaney	Found this. http://www.jdm.homepage.dk/easypic.htm Is "R" needed?

29th November 2007, 03:53 AM	(permalink)
Gayan Soyza	Your programmer will give you trouble in a small variation on your comport voltages & in your supply.In your programmers it needs external 5V.If the voltage exactly 5V you don't need the resister.Most JDM type uses 5.1 zenners. Try making the JDM programmer here is the simple version of that working well. No need external supply. http://www.semis.demon.co.uk/uJDM/uJDMmain.htm __________________ Gayan My Website http://gsmicro.blogspot.com/ Last edited by Gayan Soyza; 29th November 2007 at 03:57 AM.

29th November 2007, 06:51 PM	(permalink)
wmmullaney	Ok, I'v seen the uJDM, kinda wanted something simpler just to start, after that I want to get a JDM programmer from Sparkfun. So, 5k resistors will work. I hope to have my projects up and running by Christmas.

29th November 2007, 07:33 PM	(permalink)
wmmullaney	What do you suggest? I don't have 50+ dollars to spend. Or to many parts to build one with.

29th November 2007, 07:35 PM	(permalink)
wmmullaney	Is the PIC16F628 compatible with the PIC16f84? Last edited by wmmullaney; 29th November 2007 at 08:01 PM.

29th November 2007, 08:30 PM	(permalink)
matc	Define "compatible" ? It's not the same part, but check the datasheets for pinout compatibility.

29th November 2007, 10:29 PM	(permalink)
wmmullaney	I meant in a programmer.