Bad Basic Stamp 2 oem chip
Matt Battle
Posts: 172
I was wondering what are some ways I can test to see if I have a bad pic16c57c or not?
-Matt
-Matt
Comments
Did you get the PIC16C57 from Parallax (or from Peter Anderson)? If not, it won't work. Parallax programs the PIC with their proprietary interpreter which allows it to make sense of the PBasic tokens. If you have a PIC from Microchip or from a distributor, it is not yet programmed and won't work. The part that you need can be found at:
http://www.parallax.com/detail.asp?product_id=PBASIC2C/P
Good luck!
peter
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Peter C. Charles
Director, Research and Technology
CyberBiota, Incorporated
Peter.charles@cyberbiota.com
http://www.cyberbiota.com
That should be the one. The things to check now are your wiring (I have triple checked things, only to find the next day that there was still a mistake!), paying particular attention to the orientation of the IC's and the electrolytic caps. Also make sure that the serial interface is wired correctly- check the wiring diagrams that can be found in the Stamp Manual. Make sure you are using a "straight through" serial cable.
What error do you get from the PBasic IDE?
peter
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Peter C. Charles
Director, Research and Technology
CyberBiota, Incorporated
Peter.charles@cyberbiota.com
http://www.cyberbiota.com
I tend to use the MAX233E chip for RS232 level shifting- it doesn't need any external caps, and is easier to use (but more expensive). I don't know how tolerant to capacitor substitutions the MAX232 chip is, but I would be hesitant to try it. For a description of the serial connection to the Stamp, look at page 28 of the Stamp Manual V2.2. You can get it here:
http://www.parallax.com/dl/docs/prod/stamps/web-BSM-v2.2.pdf
peter
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Peter C. Charles
Director, Research and Technology
CyberBiota, Incorporated
Peter.charles@cyberbiota.com
http://www.cyberbiota.com
Also- if it is any comfort, I have been using PIC microcontrollers for 15 years and have never fried one. It is very unlikely that you have killed yours. They are remarkably robust.
[noparse];)[/noparse]
peter
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Peter C. Charles
Director, Research and Technology
CyberBiota, Incorporated
Peter.charles@cyberbiota.com
http://www.cyberbiota.com
Post Edited (Matt Battle) : 12/29/2005 2:15:20 PM GMT
The PICs are very very tolerable microcontrollers... I've been using a speaker directly from a free pin by the FREQOUT command... Only imagine the current needed for the speaker to work... If you burn your PIC you are a hero... You must directly connect a pin ether to ground or the Vin/Vdd to do that...
Regards, Provas, GReece
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-Rule your Destiny-
--Be Good. Be Bad. Be Provas--
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Sid Weaver
Do you have a Stamp Tester yet?
http://hometown.aol.com/newzed/index.html
·
I just looked at the schematic that you posted (from the WeetHet website)- Provas is correct, there does seem to be an error in the schematic. The MCL (pin 28) of the PIC must be pulled high to function. Usually this is accomplished by connecting the pin to the VDD via a 10K resistor. Without the pullup, the PIC sits in a continuous state of reset and will not respond to any signals. If you check the shematic for the BS-2 OEM on the Parallax website (http://www.parallax.com/dl/docs/prod/schem/bs2oem.pdf) they also do this.
peter
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Peter C. Charles
Director, Research and Technology
CyberBiota, Incorporated
Peter.charles@cyberbiota.com
http://www.cyberbiota.com
I didn't mean·a chip·tester.· I was talking about the Basic Stamp 2 OEM kit.· But·I might get a chip tester just becuase it would be useful.
Peter-
When you said "they also do this", do you mean that the schematics on the parallax website also has the MCL pin wired wrong and I should have it wire to the Vdd.· I am just lost to what Vdd do you mean??· You mean to the postive +5v line coming out of the 5v regulator?·besides the 10k resistor is there any speical way I should connect it to with a reset button or switch?
-Matt
·
Sorry, I was in a hurry and wasn't being clear. The BS-2 OEM schematic shows the reset (MCLR, pin 28) with a pull-up resistor to the +5 V (VDD). This is correct, as the PIC requires a logic high on this pin to run. The device is reset by pulling the line low; by using a resistor and pushbutton to ground (a reset button) or by toggling the DTR line on your RS232 interface (this is how the Parallax software gets the attention of the Stamp to reset it and put it into programming mode to load a program). If you add a 4.7K to 10K resistor between the MCLR (pin 28) and your +5 V (VDD- the regulated positive feed for the PIC), I suspect your Stamp will live.
peter
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Peter C. Charles
Director, Research and Technology
CyberBiota, Incorporated
Peter.charles@cyberbiota.com
http://www.cyberbiota.com
Thanks when I get home in a few days from vacation, I will connect the MCLR pin to the +5v and see what happens. Hopefully thats all I have been doing wrong. That would be an easy fix. This problem has put me a week behind my goals to my main project. Thanks and have a good new years.
-Matt
Regards, Provas, GReece
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-Rule your Destiny-
--Be Good. Be Bad. Be Provas--
-Matt
Yes, it definitely should be. The PBASIC Stamp Editor does some physical testing of the PC ==> Stamp wiring connection as part of its "sanity" checks, but it also expects a reply from the Stamp so that it knows that there is actually a Stamp on the other end, and not some other unknown IC. All of the wiring should be complete before testing will be successful.
Regards,
Bruce Bates
-Matt
10K, 4K7·1/8W, should be OK.·
What about your 9-pin connector -- how certain are you of it?· Is the MAX232 included (I ask this because you asked about the Resonator and the EEPROM)?· If it is, you should have +10V·from its Pin 2 and -10V at its Pin 6.
Wherever in your schematic it has "+5V" you should be able to measure 5V from Ground (DC).· If not, why not?
Isn't "saving money" fun?
Anything like what? What do you mean how certain of my 9-pin connector am I?? Well, its new and I have loop back showing up as yes in the stamp editor? So I am sure that my 9-pin connector works. Doesn't echo supposed to show up as yes also? No I am not using the MAX232 right now. I am using the BS2 schematic. That is the problem about the +5v, a lot of places I test is showing up as 1-2V or even less. Also my voltage regulator is very hot, which is not good. The reason I am doing it like this is not just to save money but to learn. I guess its back to beginning again. I might work on other things then this stamp circuit.
-Matt
The overheated regulator and low voltage say to me that there is either a short on the output side (the +5 VDC regulated DC line), or there is an overload on it, or the regulator is wired incorrectly. First re-check the wiring of the regulator, and the part number to make sure it's what you expect it to be.
If that is all okay, next set your voltmeter to semi-permanently connect to any one of the presently too low test points. Then, connection by connection, follow the regulated DC line from the regulator outbound, removing each of the connections to that line individually. At one point the voltage will JUMP back to +5 VDC and that's when you've identified ONE short or overload. Fix that, and if any of the test points STILL reads low, continue on until you've located ALL of the improper connections.
Regards,
Bruce Bates
Post Edited (Bruce Bates) : 1/12/2006 7:14:21 AM GMT