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lassethomsen
02-15-2007, 09:26 PM
Hi.

I have a propeller chip installed on a propSTICK, and last nigth i was trying to test the propeller, hence get a led blinking. It worked perfectly, but today the Propeller tool tell me "No Propeller chip found on any COM port".

I have connected a +9V DC to the Vin on the propSTICK, just like last nigth. When meassuring over the Gnd and 3.3V pins on the propeller the result i 3.25v, so it looks okay.
But is there anyother way i can test the propSTIC/propeller setup? Or should i just assume that my propeller chip is dead, (and not the propSTICK) and buy a new Propeller?

bambino
02-15-2007, 09:31 PM
You have probable already checked, but has your com settings changed or been moved around.

lassethomsen
02-15-2007, 09:35 PM
Yeah nothing has changed, since i didnt do anything the first time. It dosnt work on any computer i have tried with so far. Its there anything speciel i should set my com-settings to?
I have only installed the Propeller tool and then used the F7 shortcut.

bambino
02-15-2007, 09:42 PM
No, I believe the IDE sets that internally. I was referring to the physical connection mostly. ·If you have a scope look for a heart beat on Xin line from the crystal.

lassethomsen
02-15-2007, 10:17 PM
XI on the propeller gives me a sinus-curve with a periode of 200ns.
With an amplitude of 2v peak-to-peak.

The XO pin on the other hand, give an far-from perfect sinus curve.

Its the okay for the chip?

Can I somehow test the RS232 interface of the propSTICK?

bambino
02-15-2007, 10:35 PM
I don't have a propstik but if you can get to the pins it should be easy to test for a signal. Using hyperterminal 115200baud, 8n1. Just hold down the uppercase "U" key to send a 50% duty cycle signal to the propstic and see if your getting a signal into the level shifter(Max3232 I think is on the Propstic) and a signal out to the Propeller.

As for the 2VPP I am not sure if that is bad or not. I checked mine some time back and think it was closer to 3PP, maybe someone else can clarify if that is within specs?

Post Edited (bambino) : 2/15/2007 2:40:55 PM GMT

simonl
02-15-2007, 10:47 PM
It's a long-shot, but try pressing the PChip firmly into the PropSTICK socket - used to work great in the old BBC Micro days!

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Cheers,

Simon

BTW: I type as I'm thinking, so please don't take any offense at my writing style http://forums.parallax.com/images/smilies/smile.gif

-------------------------------
www.norfolkhelicopterclub.co.uk (http://www.norfolkhelicopterclub.co.uk)
You'll always have as many take-offs as landings, the trick is to be sure you can take-off again ;-)

lassethomsen
02-15-2007, 11:30 PM
Hi

Pressing the propeller into the socket again didnt change anything.

Regarding measuring the Rin on the MAX3232 chip, what would the peak-to-peak voltage be, and how fast should the periodetime be when pressing "U" in hyperterimal?

·

bambino
02-15-2007, 11:50 PM
On the PC end you will see +/-11V, on the Prop side You should see 0 to 3.3V,

Although the Prop should read it if the High is 2.5V or greater.

For a Baud of 115200 1/x gives 8us.


Post Edited (bambino) : 2/15/2007 3:54:43 PM GMT

Chris Savage
02-16-2007, 12:13 AM
Just out of curiosity, how were you powering the module?

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Chris Savage
Parallax Tech Support

bambino
02-16-2007, 12:15 AM
I've got to go for the day, but from what you've told me I see no reason to chunk the Propeller just yet. You might check you com properties in the device manager to see if windows has them flagged or something. Other than that I would just get the Propstic schematic and ohm out your connections to see if you might have some cold solder joints, or shorts and opens.

Good Luck,

lassethomsen
02-16-2007, 12:34 AM
Chris Savage (Parallax) said...
Just out of curiosity, how were you powering the module?


I have attached a 9volts Duracell battery to the Vin + Gnd on the propSTICK.
Thanks for your help bambino, tomorrow I will try with my scope and see if there is a signal from the RS232 interface to the MAX3232 chip.

Chris Savage
02-16-2007, 12:43 AM
Even though your 3.3V seems to be close, since this is a battery I would recommend trying a fresh one or another power source just to rule out any problem with the battery.

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Chris Savage
Parallax Tech Support

lassethomsen
02-16-2007, 12:49 AM
Hi.

I have just tried with another new 9v battery and no luck. Tomorrow i kan try with an real PSU, to see if it changes anything.

lassethomsen
02-16-2007, 07:24 PM
No luck with an real PSU. Next step is trying measuring the MAX3232 chip.

Stan671
02-17-2007, 05:41 AM
I had a little trouble with my PropStickUSB when I first tried it.· The IDE reported that it could not find a Propeller when I tried to Identify (F7).· I tried several different power supplies and different USB cables.· I thought my Prop was dead out of the box.

Then ... mostly as a way of venting my·frustration ... I just tried a series of·repeated pressing of the reset button on the PropStickUSB and pressing F7 (Identify) on the PC and somehow it finally woke up and has been working perfectly ever since.

Go figure ...

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Stan Dobrowski

lassethomsen
02-20-2007, 12:18 AM
Hi.

Got the new chip today, everything worked like a charm. So im guessing that the old chip some how died.

Back to the fun stuff, coding.