Your efforts have been a source of inspiration for many.

The work you have done is/was excellent.

I have not tried the Maplin version, but I do use on a daily basis the DIY
programmer - it's great.

You get my vote.

Rgds...

...Andy
At 17:59 10/02/99 +0000, you wrote:
>>   Hey, Andy, I've been hinting - send me a web reference to or
>>   e-mail of the Maplin programmer circuit and let's try and get
>>   it going.
>
>The Maplin programmer is more or less the same as the ASCII sketch in
>the file pic84pgm.zip (all programs mentioned are in my PIC archive).
>It should work with the software in pic84v05.zip and numerous other
>programs available on the web.  It is a kit and I'm sure some people
>have difficulties because they have not built the thing correctly.
>Other problems are for the most part fixed by using a short connection
>from PC to programmer, adding a 4.7k pullup from ACK to +5V and, like
>a lot of these parallel port designs, adding a couple of 100-470pF
>caps from RB6/7 to ground.  From what Andy says Maplin don't give
>users a lot of support.  They have bundled some of my old software
>with their kit and so I get a few moans sent to me, but to be fair I
>also hear from people who didn't have any problems.  PC speed is often
>cited as a problem and that may be true for some PCs.  I tried hard to
>make the pic84v05.zip software as processor speed independent as I
>could but I rely on the PC timer chip working the way I think it
>should (you can check that by running tchk.exe from topic03.zip).
>
>> > otherwise I recall that people have mantioned problems with incorrect
>> > diode sourcing on the D.T. programmer.
>
>I have at least 5 programmer designs on my web site and I'm not sure
>which is the most likely culprit here - perhaps my 16C5X programmer as
>I specify a Schottky diode for one component.
>
>> The design does appear to be a bit dodgy and substitution of the wrong
>> *brand* of part could be the problem.
>
>Sorry about that.  Apart from some head scratching when I was putting
>together my very first prototype I've never had any problems with my
>designs.  Because of that I was happy to make them available for free
>so that others could have some fun too.  If my designs are really
>"dodgy" and causing people lots of frustration it would pain me a lot.
>Nowadays I can only deal with a fraction of the mail that my
>programmer stuff and web pages attract (which gives me a permanent
>guilty feeling) but at one time I spent a lot of time trying to help
>people get their programmers working.  I wasn't 100% successful as
>trying to fix software/hardware by e-mail is not easy.  On balance I
>think my stuff is still useful but perhaps I'm wrong.
>
>David
>--
>http://www.man.ac.uk/~mbhstdj
>