GBS301: Any luck?

gerundronaut

There are a couple of old posts about people trying to use the GBS301 to program their BOE-Bot. Has anyone figured out a way to make it work?

Some have said it's not possible. Does anyone know why that is, aside from it using some sort of special signaling? (I'm curious what is special about it, basically.)

I am able to read data from the bot, but when I try to ID the stamp I get the message "No Basic Stamp detected" when the GBS301 is connected directly and "Basic Stamp 2 detected, but is not responding" when I jumper pins 7 & 8 (CTS/RTS) together. I do not have a serial port on my computer, so this (or something similar) is my only option for programming. (well, unless I buy a usb->serial adapter, but there's no guarantee that would work, for the same reasons.)

Post Edited (gerundronaut) : 7/25/2009 4:03:12 AM GMT

Mike Green

You cannot use any kind of wireless link between the Stamp Editor and a Stamp for programming (or identification). IT IS NOT POSSIBLE. The time delays inherent in these links prevent it from working. It cannot be made to work.

See this thread: http://forums.parallax.com/showthread.php?p=826193

USB to Serial adapters using the FTDI chip generally work. Parallax uses this chip for the adapters they sell. I've also used a Keyspan High Speed Serial Adapter for years with Stamps and Propellers without problems.

gerundronaut

I don't fully understand. I'm looking at the bstamp SF project code and I see in BS2_id() that the code sends a single-letter "command" to the chip, and expects to get a response. (Well, first it eats the echo'd character and then reads the response). If the response is char 190, it goes on to investigate further.

In my case, the command is going out, but the response (excluding the echo) is showing as char "W", as in "Waiting for reset...", from the looping program that's running on the BS2 right now. I've modified the bstamp_run program to flood the chip with "B"'s, but the chip never responds with anything but echo and the constant "Waiting for reset..." program. Since it's just a single 8-bit byte, what timing issues could be coming up?

Do you have more technical details about why the chip is not responding to the command? About the timing it expects?

Post Edited (gerundronaut) : 7/25/2009 5:29:01 PM GMT

Mike Green

You need to include the code you're using as an attachment to your message. There's lots of Stamp sample code available and it's not clear what you're talking about.

Unsoundcode

Hi , before you transmit the "ID" characters you have to put the Stamp into reset in a special way , once you have succesfully reset the stamp you transmit "B" <wait· echo/response> "S" <wait· echo/response> "2" <wait· echo/response> 0 <wait· echo/response>

This is explained in "Basic Stamp Programming Protocol" a part of the Tokenizer documentation

The reset is also described in the same documentation and is a combination of a pulse on the DTR line and a break state of the TX line.

The timing as a whole is very fine and as far as I know unachievable over a rf link.

I have toyed with the idea of using an additional Stamp attached to the "target" Stamp and used as a programming module but have yet to put it into action

Some·of my thoughts have been guided by Tracy Allen's documentation at the following link http://www.emesystems.com/BS2clone.htm

Jeff T.

·

gerundronaut

Thanks Mike Green and Unsoundcode. I see now one of the problems here: apparently GBS301 does use the DTR line. That plus the timing requirements (2ms, 36ms, 20ms) with the 2ms being longer than it takes to send a byte make it pretty much unworkable. Bummer. I considered rigging up a couple of 555s to handle just the DTR/TX reset, but I figure it's better to just get the "sure thing" USB cable.

FWIW, I was referring to http://bstamp.sourceforge.net/ .