AXE091 download resistors

[StigOfTheDump]

Hi

My AXE091 has a 10k pull down resistor and a 22k line resistor on the 18, 28 & 40 pin sockets. On the 8, 14 & 20 pin socket it has a 22k pulldown resistor and a 10k line resistor.

I thought maybe the components had been put in the wrong way round, but the photo in the manual shows them as mine are.

http://www.rev-ed.co.uk/docs/axe091.pdf

Picaxe manual 1 shows the first scenario to be correct and makes no mention of different set-ups for different chips.

Does anyone know why this is?

Has anyone got one to see if it is the same as mine?

Are any problems likely to occur if I just ignore it (if in fact, it is wrong)?

 

[hippy]

Interesting, and it does seem to be the same on my AXE091 ( though it's not the latest production version ).

The interface should be 10K pull-down, 22K in-line series resistor, for all PICAXE. For the 8/14/20-pin PICAXE on AXE091 these do appear to have perhaps been fitted swapped over on at least some boards.

We will investigate the issue and thanks for spotting that.

 

[BeanieBots]

If you are using the AXE027 download cable, it won't make any difference.
If you are using a +/-12v serial port, then probably a good idea to swap them over.
I'll leave it to Rev-Ed to check if the latest build is OK.

 

[john2051]

Hi,
I have four axe091s, it appears the resistors are definately wrong the way round on all four boards. It only seems to affect the 20 pin sockets. As luck would have it, I use the axe027 to program them. However, I think I'll put them right just in case!!!
Thanks for finding this out.

regards John

 

[Dippy]

Well spotted. But does it really affect operations?

 

[john2051]

Hi Dippy,

As far as I can tell, you would never know, my 20 pin picaxe chips behave ok, and I've had no upload issues.

regards John

 

[StigOfTheDump]

I'm using an AXE027 so it won't affect me.

If there really are no issues with any other set up, then it is probably easiest to fix that "Typo" in the manual.

 

[Technical]

It does look like some of these have been incorrectly manufactured by the subcontractor, so thanks for pointing this out.

In practise it will work fine and so can be ignored, particularly if only using the AXE027.

If you really want to correct it you only need to change one resistor - change the 10k resistor to a 22k. Having a 22k pull down instead of a 10k is no problem and so can be left anyway.