Velleman Programmer

[david miles]

Hello.

This is my first attempt at PIC programming. I have the 8048 programmer.

When I try to "write", I get the message " K8048 not found at COM 1".

I already have Picaxe programme editor installed on my PC, and I am wondering if there is a conflict, but I do not know how to configure COM 1.

Also, I could not find a serial cable to use with the 8048 programmer, so I made up a temporary one, connecting pins 2,3 and 5 "straight" not crossed in any way.

Has anyone any idea as to why things are not working?

David Miles.

 

[drage]

what software are you using to program the pic? / write to it with?

 

[david miles]

Hi drage.

I am trying to get the sample "running led" programme working, using the supplied 16F727 micro. The software is included with the programmer on a mini disc. Compiling uses MPASMWIN and programming uses PROGPIC2.

David Miles.

 

[tunedwolf]

Your cable has to be wired 9pin to 9pin straight through plug to skt going from what I see on the schematic...it is not actually using an rs232 protocol, rather, it's using the com port to control the various switching transistors etc

 

[Nigel Goodwin]

Yes, it's not really a 'serial port' programmer, it's just connected to the handshake lines.

 

[drage]

i too purchased this pic programmer from maplins recently.

I found the supplied serial cable worked fine..

if you're on windows its quite simple to see whats on what com port:
go to control panel, system, then hardware, then device manager.
From here you can look at :
(ex): Ports (COM & LPT...)

hth
Paul

 

[david miles]

Thanks for replies.

Can anyone explain how I can find out which software ( Picaxe or PIC ) is using COM Port 1.

David Miles

 

[Nigel Goodwin]

Thanks for replies.

Can anyone explain how I can find out which software ( Picaxe or PIC ) is using COM Port 1.

For a start you need a correctly wired lead, it might then work OK? - it certainly won't at the moment, as you don't have it connected at all.

 

[david miles]

OK.

Here is a picture of my "made up" cable.( I hope it comes through ) Can you say if it looks OK?

David Miles.

 

[Nigel Goodwin]

You've not been reading the previous posts! - it's NOT a serial port programmer, it's a programmer that connects to the handshake lines of the serial port. Out of the three pins you've wired only ONE of them is used, and that's the ground connection.

If you don't want to wire all 9 pins, check the circuit for the programmer and see which ones are used - it's got to be more than three, there's at least Gnd, Data, Clock and MCLR - and possibly Vcc as well.

 

[david miles]

I don't really understand what you said about serial ports and handshaking, but never mind, I will wire up all the pins ( straight through ) and see if that changes anything.

David Miles

 

[Nigel Goodwin]

I don't really understand what you said about serial ports and handshaking, but never mind, I will wire up all the pins ( straight through ) and see if that changes anything.

As I said before, just look at the circuit diagram, this clearly shows the only pins connected are, 3, 4, 5, 7, 8, and 9 - there's even a wiring diagram for the lead in the assembly instructions!. BTW, pin 3 (and pin 9) are only used to provide a negative bias voltage for the RS232 level converter on the programmer, and to switch between programming and normal modes.

 

[tunedwolf]

something about leading a horse to water comes to mind...

 

[david miles]

Hi All.

I have made up a cable using all 9 pins and it works fine. Thanks for pointing me in the right direction. I would like to say that, apart from the fact that I don't have the assembly instructions or the circuit diagram, I do not find this whole area of electronics very easy to get to grips with. I am at a real entry level, but I am trying!

David Miles

 

[Nigel Goodwin]

I would like to say that, apart from the fact that I don't have the assembly instructions or the circuit diagram

Neither do I (obviously), so I just looked it up on the Velleman website!.