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GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 05:18am 16 May 2008

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Has anyone noticed that output 2 of an axe 05M goes high when an ADC input function is called. This happens on the simulator. I normally use this as a PWM output excusively.

This little program demonstrates:-

main:
pause 2000
high 0
pause 1000
high 1
pause 1000
high 2
pause 1000
high 4
pause 1000
low 4
pause 1000
low 2
pause 1000
low 1
pause 1000
low 0
pause 1000
readadc10 4,W0
goto main
end

The usefulness of the output 2 is limited when this occurs. .. .. Gordon.

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Gill

Senior Member

Joined: 11/11/2006
Location: Australia
Posts: 669

Posted: 10:51am 16 May 2008

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Gordon,
I ran that little exercise through the simulator and all seemed to go OK. the only comment is that you would need the line
let dirs = %00000111
added before
readadc10 4,wo
to change pin4 from output to input. Though I'm guessing this was just an trial setup to highlight the glitch you have.

Then I ran this (your test with debug added)(pin 0 removed as used for debug) on an actual 08m and still found no fault with pin 2.

#picaxe08m

main:
debug
pause 2000
;high 0 ; can't use 0 high & low when using debug
;pause 1000
high 1
debug
pause 1000
high 2
debug
pause 1000
high 4
debug
pause 1000
low 4
debug
pause 1000
low 2
debug
pause 1000
low 1
debug
pause 1000
;low 0 ; can't use 0 high & low when using debug
;pause 1000
readadc10 4,W0
debug
goto main
end

Maybe you could show us an excerpt from the actual code where simulation is sending pin 2 high when readadc10 is used? As I say, I can't duplicate the error yet.

was working fine... til the smoke got out.
Cheers Gill _Cairns, FNQ

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 12:34pm 16 May 2008

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Hi Gill,

I have pasted the modified code that you posted, and I present the outputs. I have included the about screen for the programmer and 2 screen dumps from the running program. One just before the readadc command, and then just after.

I will test with a chip in the real world. There may be something with the version of the programmer.

There is no way that the pin 2 output should change state in this way.

I will continue tomorrow. .. Gordon.

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GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 01:56am 17 May 2008

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Hi Gill,

I have tested on a chip in the real world, and it is OK, so there must be something up with the simulator. .. Gordon.

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Gill

Senior Member

Joined: 11/11/2006
Location: Australia
Posts: 669

Posted: 03:59am 17 May 2008

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G'day Gordon,
Yes, I see what you say with pin 2 high. most strange.
Good that it tests OK in the real world.
I had installed the little update that takes V5.1.5 to V5.2.0. Perhaps it is a glitch in the software that has been fixed in the update? I bet you find the update before I send this so hopefully all good with simulation now.

I had one where the readADC value always came out incorrect. I added small pauses to no avail then found if I repeated the same line the second reading was correct. Just a glitch in the chip I guess, at least I found a workaround for that one.

was working fine... til the smoke got out.
Cheers Gill _Cairns, FNQ

Gill

Senior Member

Joined: 11/11/2006
Location: Australia
Posts: 669

Posted: 06:12am 21 May 2008

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Came across this same/similar problem on the official PicAXE Forum here
There's not much discussion and it doesn't go anywhere. At least that shows it's not a fault exclusive to your software.

was working fine... til the smoke got out.
Cheers Gill _Cairns, FNQ

SparWeb

Senior Member

Joined: 17/04/2008
Location: Canada
Posts: 196

Posted: 07:18pm 27 May 2008

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I found an excellent website, including known bugs, here:

http://www.hippy.freeserve.co.uk/picaxe.htm

Steven T. Fahey

Gizmo

Admin Group

Joined: 05/06/2004
Location: Australia
Posts: 5012

Posted: 09:05pm 27 May 2008

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Thats a good site, thanks for the link Steven. I'll add it to my PicAxe page in the near future.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 03:08am 28 May 2008

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Hi Gizmo,

I did not find a reference to the AXE-08M in the link that was provided above.

I have just perused the Microzed website and found a useful companion to the picaxe. The serial LCD. I had toyed with making my own for the BS2. The unit is not too expensive. A single output is needed and + & -. The unit even works on the output0, programming port of the picaxe 08M, so 4 inputs are still available.

This sort of display will have all sorts of uses. Gordon.

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