View Full Version : BS2 is not detected

03-14-2010, 03:17 PM
· hi....

···· i am a BS2 user.when i try to connect my Boe-Bot robot to my pc using PBASIC Stamp editor, my BS2 is detected at all.
···· i tried to change my settings as per given in the pdf file downloaded from parallax site.but·i cant find any instructions tat
···· is given in pdf(i didnt find FIFO BUFERS in my system)...
···· the name of pdf file is robotics v2.2.pdf

········ PLS·HELP ME......·

Mike Green
03-14-2010, 08:03 PM
Almost all problems like this are because of a few things ...

1) The Stamp must have power. Make sure, if you're using a battery, that it's fresh.

2) The Stamp must have a working serial connection to the PC. Make sure your cables are ok.

3) If you're using a USB adapter, make sure you have the correct manufacturer's USB driver installed. The default Windows driver will not work for programming

4) Not all USB to serial adapters will work for programming. Those that use the FTDI chip will work. A few others will work.

There's more information in the "sticky threads" at the top of the thread list in this forum.

Paul Romsky
03-16-2010, 06:48 AM

I have a USB Board Of Education (BOE) with a BS2 stamp and the suggested 9VDC power supply.· Everything was working fine for a few hours, I was making a LED blink (only one LED and limted to 8mA), using PWM to make·the LED change brightness, I was even getting values from a potentiometer.· All was fine, then when I went to explore the BUTTON command, the BS2 locked up and now when I try to program it, all·I get is "No BASIC stamps found".· I see Loopback and Echo are "Yes" and I get both colored programming lights on the BOE.· I tried everything including uninstalling and reinstalling the software and USB driver but I still can't program the BS2 anymore.·· When I was simulating a push button switch (I didn't have one on hand), I used a wire that I moved from VDD to VSS (for a active low button).· I was careful on how I did this and I do use a wrist strap to prevent ESD - the pin involved was indeed set to an INPUT.· I don't think I blew up the BS2 so I started to look at some signals.· I don't have a meter or a scope on hand so I made a cheezy logic probe from a 470 ohm and a LED.· The ATN signal does not seem to go very high (not too bright) when I try to program the BS2.·

Do you know what voltages levels I should see on the ATN signal on the BOE?·

It either the Software, the BS2, or the transistor on the BOE that drives the ATN signal.·

Any ideas on how to determine whre the problems is located?.·

The BOE is about $100 and the BS2 is about $40.· Both are fairly costly considring the relative size of the system.


03-17-2010, 08:45 AM
Jerish, like Mike had said, check your power supply (in the booklet it says to use fresh batteries). If that doesn't work then make sure your BS2 in in right (follow the diagrams in robotics with the Boe Bot which I am assuming that you have). And if that doesn't work, be sure none of the pins are bent back or broken off, and make sure the the micro-controller is inserted the required 3mm into the Boe micro-controller socket. Also make sure that your Boe is in first gear. By following those steps you should come to a positive conclusion.

Change is inevitable - except from a vending machine.

Robert C. Gallagher

03-17-2010, 08:45 PM
I just got a BOE Bot kit and started to play with it. I found exactly the same problem as the one originally described. I tried to work this out on both an XP Pro system and a VISTA system with no results. I did pick up the tip about the chip being seated properly. Mine wasn't. However, when I tried again, I got the same result -- BASIC Stamp not found.

Mike Green
03-17-2010, 09:29 PM
Paul Romsky and BPS,
If you were to browse through this forum's threads, you would find a lot of examples of the same question and you would also find that, in the vast majority of the time, my statement is correct. Most of the time, replacing batteries or using a different AC power adapter has gotten things to work. Often it's the serial connection, anything from a bad cable to a USB to serial adapter that doesn't work for programming a Stamp because it's cheap and doesn't implement one of the control lines properly. Sometimes it's the USB driver on the PC. Occasionally it has been a problem with how the Stamp has been installed in its socket (bent pin, module not seated in socket, installed backwards). Every once in a great while, it has been a defective Stamp or Board of Education. Both the Stamps and the BOEs are tested before packaging.

We're not going to be able to debug your problem in a forum setting other than to tell you what to look for as the cause in the great majority of cases. If you've checked carefully, tried the things suggested, and it still doesn't work, you may indeed be one of the rare, unlucky cases where you have something defective. Parallax does support their products. Call their tech support people. They'll make sure that you've tried the things we've suggested (because you'll get a working system immediately that way). If it still doesn't work, they'll send you a replacement.

03-18-2010, 10:06 AM

if you have read through all of the forum posts that specify with help in this topic and still have the persisting problem, post pictures of your setup (particularly the BS2 in its socket, the serial/USB connected to computer and the whole Board of Education itself) I or whoever posts before me will try and identify the problem.

Change is inevitable - except from a vending machine.

Robert C. Gallagher

03-18-2010, 07:20 PM
I'll do that, hoepfully, later today but I'm sure that everything is assembled the way the manual describes. I have been in contact with Support via email. Joshua Donelson suggested that I modify the latency setting in WINDOWS for the USB port. I did that and it still didn't work.

03-19-2010, 04:00 AM
I took your suggestion, went to the local pharmacy and purchased a brand new 'sell-by date-2014' 9 volt battery. I installed it and tried to run a little program. It workedI had to press the reset button to see it work but it worked. Now I'll try using different AA batteries and see what happens. Thanks again.

03-19-2010, 05:07 AM
One tip:
Buy cheapest multimeter - maybe not perfect accuracy, but perfect first tool for elektro - beginners.


Every problem·have at least one·nice, simply and·wrong solution.

03-21-2010, 11:06 AM
One more thing about the battery issue, or a plug in power supply for that matter is that the battery can be rapidly discharged or the power supply voltage can be dropped so low that there is not enough left to supply the minimum voltage for the stamp via the brownout detector. Even with a "new" battery or a plugin power supply your circuit can pull enough current to drop the voltage low enough to disallow programming. When I see that dreaded "no basic stamp found" message the first thing I do is disconnect the external circuitry from the stamp and try downloading the program. Almost allways this cures the problem. Then it's time to troubleshoot the circuit. I have many bs2 modules,OEM versions on homebuilt PCBs, and propellers. I have made more mistakes than I have stamps and they are all still working with the exception of one bs2ic that has a P3 that doesn't work (my bad, OOOPS.··Electrical smoke sure has a certain smell to it!). I'm not sayin that you shouldn't check you circuit before you power up, but to me these proccesors are built like a tank!