Connectiong to computer

[magester1]

I've once asked here if there was any risk in connecting some circuit (made by myself) to the motherboard. I was told that there was if something BAD happened, of course.
My question now is about a PIC programer, not the programming itself (that's why I posted it in this forum and not the Microcontrolers one).
I've built the next programmer: PIC Programmer for Windows - Help Index
and I was wondering if there was any risk with THAT for my computer. I'm using a PC power supply as the regulated power supply by the way. I've got one of those modern (at least it's modern where I live) motherboards which got almost everything included in them, ASUS M2N-E Sli.
Besides, I've tried it out on a very old computer (Pentium II) and it seems to work fine.

Thanks for your help.

 

[Space Varmint]

I don't see any problem with it.

 

[magester1]

I guess I should be a little more "paranoid" with my question then, xP
I meant if by any chance I solder something incorrectly. Would THEN be any risk? I'm guessing that's some pretty stupid question actually, but what I mean is, for instance, it may not work because of that mistake but not damage my motherboard...

 

[Reloadron]

They took the time to mention this in the link:

If a precise (regulated) 12.7 V DC power supply is available, the voltage regulator (78L12, with D7, C2..C3) is not needed.

They seem pretty intent on 12.7 Volts rather than 12 Volts to the point they used D7 in the common leg of the 7812 to get the higher output voltage. However, if it works I guess it works for you with 12 Volts.

Rather than worry about soldering anything why not just use an unused connector from the computer PSU, like maybe an unused hard drive or floppy connector? Typically you could hack a fan adapter designer with a 4 pin Molex connector and have your 12 Volts (Yellow) and Common (Black). I just don't see a need to solder anything to your motherboatd or the PSU if you have an unused connector available.

Ron

 

[magester1]

I think you got that wrong, I'm not soldering something to the motherboard. I ment to ask if there was any risk for my motherboard through the Serial Port if I made some mistake when building the programmer.

 

[Reloadron]

I think you got that wrong, I'm not soldering something to the motherboard. I ment to ask if there was any risk for my motherboard through the Serial Port if I made some mistake when building the programmer.

My bad, sorry.

No, just watch what you are doing. I program from the USB and RS232 ports with boards I have built. Obviously there is a small risk but short of buying something prefabricated there is no alternative. Just watch your connections and check things before actually connecting.

Ron

 

[magester1]

My bad, sorry.

No, just watch what you are doing. I program from the USB and RS232 ports with boards I have built. Obviously there is a small risk but short of buying something prefabricated there is no alternative. Just watch your connections and check things before actually connecting.

Ron

Well, I've already made it and used it more than a few times, in another PC, and it worked perfectly. So I'm guessing everything will be fine.
By the way, I built it with a perfboard, is there anything I can put or cover the copper side with so to avoid it touching something and creating shorts or static?? I mean, cover all the conections, wires, whatever there is.

 

[Reloadron]

I used perfboard and would you believe wire wrap?

I placed it on nylon standoffs which worked out well. My power supply was a 12 Vot wall wart I have driving a 7805 as I only needed 5 volts. The nylon standoffs worked out well though. They help keep all those wire wrap pins sort of isolated from bumping into things.

Ron