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Bad Basic Stamp 2 oem chip — Parallax Forums

Bad Basic Stamp 2 oem chip

Matt BattleMatt Battle Posts: 172
edited 2006-01-24 01:16 in BASIC Stamp
I was wondering what are some ways I can test to see if I have a bad pic16c57c or not?

-Matt
«13

Comments

  • PJAllenPJAllen Banned Posts: 5,065
    edited 2005-12-29 01:03
    Is this a kit?· Did you make it?· Did it work once before?· C'mon -- out with it.
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-29 04:27
    LOL nope my secrets haha. okay okay. Well, its not a kit its the PIC16C57C chip with the MAX232 and I was using the schematics found here http://www.weethet.nl/english/basicstamp2_homebrew.php. I took everything off the breadboard and rewired the breadboard and still no luck. So I am lost to what is wrong. Any ideas?
  • cyberbiotacyberbiota Posts: 79
    edited 2005-12-29 04:49
    Matt-

    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Peter C. Charles

    Director, Research and Technology
    CyberBiota, Incorporated
    Peter.charles@cyberbiota.com
    http://www.cyberbiota.com
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-29 05:02
    If I am reading my invoice from parallax correctly I got Item PBASIC2C/P, description: PIC16C57C-20/P. I thought that was the right chip for that schematics?
  • cyberbiotacyberbiota Posts: 79
    edited 2005-12-29 05:15
    Matt-

    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Peter C. Charles

    Director, Research and Technology
    CyberBiota, Incorporated
    Peter.charles@cyberbiota.com
    http://www.cyberbiota.com
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-29 05:20
    yea there is something wrong which I don't know the problem to. It might be the capacitors that I am using. I got the NP ones, I don't know how much of a problem that will make. Also in IDE, it flashes scanning and then yes comes up for loopback and echo. So up to the db9 on the breadboard everything is good from what I can tell. I am still looking for other schematics to show me how to connect the stamp to the computer.
  • cyberbiotacyberbiota Posts: 79
    edited 2005-12-29 05:40
    matt-

    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Peter C. Charles

    Director, Research and Technology
    CyberBiota, Incorporated
    Peter.charles@cyberbiota.com
    http://www.cyberbiota.com
  • cyberbiotacyberbiota Posts: 79
    edited 2005-12-29 05:42
    Matt-

    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Peter C. Charles

    Director, Research and Technology
    CyberBiota, Incorporated
    Peter.charles@cyberbiota.com
    http://www.cyberbiota.com
  • ForrestForrest Posts: 1,341
    edited 2005-12-29 11:32
    What are you using to power your BS2 - batteries, a regulated power supply or an unregulated power supply? I noticed there wasn't a voltage regulator in the schematic you linked to, so you'll need to build your own voltage regulator circuit (or use a regulated power supply) to supply +5 VDC +/- 0.5 V. Here's a simple +5 VDC circuit that you can power from batteries or an unregulated power supply www.epanorama.net/circuits/psu_5v.html
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-29 14:10
    I am using a L78S05CV 5.0v with a 10uf capacitor to regulate a 9v adapter down to 5v. I tested the volts coming out of the regulator setup and it is at 4.85 volts. Is that to low to run the chip?

    Post Edited (Matt Battle) : 12/29/2005 2:15:20 PM GMT
  • ForrestForrest Posts: 1,341
    edited 2005-12-29 18:00
    The BS2 will run at 4.5 to 5.5 volts - so you should be OK. I noticed the schematic you linked to has some conflicting information on crystals/resonators. If you bought the ceramic resonator from Parallax, then it doesn't need the 22pf capacitors. However if you used a crystal (typical metal can body), then you will need to use the 22pf capacitors.
  • Steve JoblinSteve Joblin Posts: 784
    edited 2005-12-29 19:59
    The schematic from Weethet also shows a R4 which is not in the schematic of the Basic Stamp...· what is the purpose of R4?
    WeetHet.jpg
    784 x 418 - 58K
  • allanlane5allanlane5 Posts: 3,815
    edited 2005-12-29 20:05
    R4 is a 'pull-up' resistor to +5 volts on the clock line to the EEPROM. This lets the PIC 'pull-down' the line, and let it 'float-up'. This also gives the clock line a solid +5 volt signal, even when the PIC is not talking to it.
  • Tricky NekroTricky Nekro Posts: 218
    edited 2005-12-29 22:54
    Is something missing? I think a 10K resistor is missing at the reset button...It is connecting the one end of the button to the +5V (not the one grounded)(I can't upload the·bitmap file, sorry...).·Without it I think it may be impossible for the PIC to reset... I don't remember exactly what it is needed for but it is needed!!! This swich must fullfill the demand for the MCLK pin to be grounded in order to reset the PIC... I don't know how to elaborate...



    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    -Rule your Destiny-
    --Be Good. Be Bad. Be Provas--


    provassiggy5yt.jpg
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-30 22:10
    I might have connected 5v power to the wrong pin and fried the chip.· Because·I have·checked and·recheck the wiring and can't figure·out whats up.·· What I might do to have one and to do test the chip is to get the basic stamp 2 kit and test the chip.· That should tell me if I got a bad chip or not.
  • NewzedNewzed Posts: 2,503
    edited 2005-12-30 22:26
    A Stamp Tester could give you the answer in a heartbeat.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Sid Weaver
    Do you have a Stamp Tester yet?
    http://hometown.aol.com/newzed/index.html

    ·
  • ForrestForrest Posts: 1,341
    edited 2005-12-30 23:07
    If you click on NewZed's link - you'll see he sells a Stamp Tester for $5.15
  • cyberbiotacyberbiota Posts: 79
    edited 2005-12-30 23:24
    Matt-

    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Peter C. Charles

    Director, Research and Technology
    CyberBiota, Incorporated
    Peter.charles@cyberbiota.com
    http://www.cyberbiota.com
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-31 05:39
    Newzed said...
    A Stamp Tester could give you the answer in a heartbeat.

    Newzed-

    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.
    cyberbiota said...
    Matt-

    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
    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
    ·
  • cyberbiotacyberbiota Posts: 79
    edited 2005-12-31 06:16
    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

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Peter C. Charles

    Director, Research and Technology
    CyberBiota, Incorporated
    Peter.charles@cyberbiota.com
    http://www.cyberbiota.com
  • Matt BattleMatt Battle Posts: 172
    edited 2005-12-31 19:02
    Peter-

    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
  • Tricky NekroTricky Nekro Posts: 218
    edited 2006-01-01 14:44
    Be aware... Not directly, it may fry the PIC... You need the 10K resistor...



    Regards, Provas, GReece

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    -Rule your Destiny-
    --Be Good. Be Bad. Be Provas--


    provassiggy5yt.jpg
  • Matt BattleMatt Battle Posts: 172
    edited 2006-01-01 16:06
    haha oh yes can't forget the 10k resistor.
  • Matt BattleMatt Battle Posts: 172
    edited 2006-01-10 12:47
    Hello, does the RESONATOR and the EEPROM need to be connect to the PIC16C57C chip for it to show up in the stamp editor program?

    -Matt
  • Bruce BatesBruce Bates Posts: 3,045
    edited 2006-01-10 13:39
    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
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2006-01-10 13:40
    You need the "resonator" in order to have a CLOCK for the PIC, it'll have no heart otherwise.· You need the EEPROM to store the program in, it'll have no brain otherwise.·
  • Matt BattleMatt Battle Posts: 172
    edited 2006-01-11 02:27
    Okay, I got everything hooked up and double checked everything but still no luck. What connections should I test to make sure they are at the right volts? I tested some and they were showing point something volts which I guess isn't good. I am using some 1/8 watt resistors. Should I swap them out for 1/4 watt? I am thinking because how easy the leads on the 1/8 watts are that they are not going into the holes on the breadboard and that could be part of my problem too. There has to be an easier way to this but I guess not haha.

    -Matt
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2006-01-12 03:37
    You ever done anything like this before?·

    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?
  • Matt BattleMatt Battle Posts: 172
    edited 2006-01-12 04:08
    PJ Allen said...
    You ever done anything like this before?

    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
  • Bruce BatesBruce Bates Posts: 3,045
    edited 2006-01-12 06:59
    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
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