40x2 download Problems

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D396

Senior Member
About 8 months ago I got a 40x2 picaxe from tech supplies. The first time a plugged into my breadboard nothing happened. I verified all my wiring still nothing. A couple months later same thing. I tried again cause now I have a project that cold actually use it and still nothing. Each of these times I rewired it. It has a steady 5v and I can program other picaxes on the same board with the same cable. Any ideas?
Thanks.
 
hippy

hippy

Technical Support
Staff member
Perhaps get hold of another 40X2 and see if that works. If not it's unlikely you've got two which are DOA so that would point towards circuit or wiring issues. If the second works but the first doesn't then maybe that was DOA as unlikely as it seems.

Other than that post a good photograph of what you have which clearly shows which hole every wire goes into, detail your power supply and download cable. Also do a continuity check of each PICAXE leg to what it connects to.
 
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geoff07

Senior Member
What is the value of your reset pullup? It looks to me like 42k but that is unlikely, so probably the colours aren't reproducing well. 4.7k-10k would be desirable. If it were wrong it could completely disable the chip temporarily.
 
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MartinM57

Moderator
Well you'll know it's bad when new one works first time in the same breadboard. When the new one doesn't work either......;)
 
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inglewoodpete

Senior Member
D396 said:
About 8 months ago I got a 40x2 picaxe from tech supplies. The first time a plugged into my breadboard nothing happened. I verified all my wiring still nothing. A couple months later same thing. I tried again cause now I have a project that cold actually use it and still nothing. Each of these times I rewired it. It has a steady 5v and I can program other picaxes on the same board with the same cable. Any ideas?
Thanks.
Click to expand...
Can you expand "nothing happened"? There must mave been an error message - they are use to help diagnose the problem :rolleyes:.

What happens when you click "Check Firmware Version"? Ie. the actual words of the error message.
 
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BillyGreen1973

Senior Member
I know this is a long shot, but have you tried swapping the serial in/out wires from the axe029 to the 40x2. All I'm thinking is, are the Txd and Rxd connections crossed?
Also, I dont see any capacitors on the input and output of the Vreg circuit at the top of your photo. This could mean the voltage supplied to the picaxe is not stable enough to allow programming.
 
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MartinM57

Moderator
Good spot BG - I can see some small caps, but no electrolytics.

@D396 - you really need to supply a schematic circuit diagram with component values rather than expect people to decode photographs. A schematic is the thing that comes before committing your components to a breadboard - so you need it yourself anyway ;)

It's a real pain that you have to do a schematic first, rather than just getting on with everything at 100mph and sticking components into breadboards and firing them up - but you will find that you will get far, far better results with an ordered approach (and a bit of time practicing your soldering ;))
 
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hippy

hippy

Technical Support
Staff member
MartinM57 said:
@D396 - you really need to supply a schematic circuit diagram with component values rather than expect people to decode photographs.
Click to expand...
That's particularly the case for things which cannot be determined from just looking at things.

That's the case with the regulator. With the resistors present it doesn't seem to be a standard 7805 in a TO-style package, so what is it, what are the resistor values ? Have you tried using a 3 x AA battery pack ?

I also can't read the markings on the PICAXE chip, and although it's not entirely important it is one of the things one would like to cross off the list as being a potential issue. I also note the earlier photos had a 40X2 sticker; is this the same chip as before or a different one ?
 
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D396

Senior Member
Okay. Sorry for the delayed reply. I just added caps-A lot of them same error as the attach photo. Swapped TX and RX same thing. The regulator is and LM317 providing 5V (My 7805 is currently in use). It is the same chip I just took the sticker of to read the markings to see if it was really a 40x2 - It is. Hooked up the 5v output from my arduino:( instead of my V reg circuit same thing.
 
hippy

hippy

Technical Support
Staff member
I don't think we're going to get much further than 'doesn't seem to work, could be dead' without doing comparative testing with another, preferably known working, 40X2.

I'd personally consider it dead in the circumstances, get another and see how it goes from there. Either that will point to it being dead or you'll become the lucky owner of two working 40X2 but no worse off than you are now.
 
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