- Hardware Communication Eailure- Sheck serial connection and power supply. err
I started getting this error on some of the OEM basic 2 stamps that I have been working with.· I bought a couple of the BASIC Interpreter chips for $11 to see if they would be a quick, cheap fix.· No luck, I get the same error.
Does anyone have any thoughts on how to fix this?
The PC identifies the chip correctly and that different power supplies do not appear to help.
Thanks for· reading this.
Does anyone have any thoughts on how to fix this?
The PC identifies the chip correctly and that different power supplies do not appear to help.
Thanks for· reading this.
Comments
·· This could be something in the programming circuitry then, if not the interpreter.· There are a few components related to that on the OEM boards.· Of course, I should ask you, are you using a laptop or USB converter?
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Chris Savage
Parallax Tech Support
csavage@parallax.com
·· I would really consider trying another power source, such as a wall adapter rated at least 300mA.· Can't hurt, right?· Also, what is connected to the pins (Any/All) while this is happening?· You aren't tying the RES line high are you?
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Chris Savage
Parallax Tech Support
csavage@parallax.com
Post Edited (Chris Savage (Parallax)) : 7/22/2005 11:50:01 PM GMT
·
Thanks
Again, appreciate everones thoughts on this. If I get an answer to this, I will summarize and post it for the next guy.
My next step would be to take an o'scope and look at the data going to / from the stamp. But I'm guessing you don't have an o'scope.
Here is alink to the BS2 OEM schematic. http://www.parallax.com/dl/docs/prod/schem/bs2oem.pdf
There is not a lot of hardware. Always do the simple stuff first. Power it up with a ammeter in series with the power supply. Watch it for a few minutes if the current starts to creep up, or jumps suddenly, it's a sign of a defective part cooking on its way to ground. Feel or sniff the parts on the board, for heat ( your nose is surprisingly sensitive to temp changes). Nothing should be warm. Q1, Q2, and Q3 can be checked with an ohm meter preferably in the diode check mode. Or just replace them for a few bucks. The four compnents Q1,2&3 and U3 translate the +/- 12 v RS232 at the PC to 0 and +5 volt RS232 used at the stamp. Q1and 2 are 2n3904 and Q3 is a 2n3906. All of which I believe are available at Radio Shack. Check online, you can even check if a store near you has it in stock. I am mystified by U3's function but it could easily be determined by googling it. Lastly, if you're convinced these are dead boards, I might be interested in buying them for cheap.
I bought a new serial cable, uninstalled activesync and tested them again. 4 of the 5 identified the bs2, but I got the same Hardware communication failure error.··VOltages look good.
Anyway, I have·just·tried these on 2 different rebooted·desktops with 2 different cables and removed activesync from both of the desktops.· I am using a ac transformer now instead of a 9 volt battery.··Can anyone suggest any other ideas?
Any idea if it would be cost effective to have Parallax diagnoise and fix them?
·· I'm sure something could be worked out, but if a new serial cable made such a difference, my next question would be, is there any way you can test these on another computer?· If you decide to go with having us check them out, contact me directly at Tech Support and I will see what I can do for you.
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Chris Savage
Parallax Tech Support
csavage@parallax.com
Thanks