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Serial Programming using a Aircable Serial adapter — Parallax Forums

Serial Programming using a Aircable Serial adapter

smoothswisssmoothswiss Posts: 4
edited 2004-11-12 16:19 in BASIC Stamp
Hi,

I recently purchased an Aircable serial adapter (www.Aircable.net). It is a bluetooth wireless replacement for a serial cable. The wireless cable works great for several serial products I have, but I cannot get it to work to program my BS2SX basic stamp, which is the whole reason for buying the aircable.

I have tried all kinds of settings, etc, but I can't use it to program the stamp. For some reason, I can get it to debug data to my computer wirelessly, and I can transmit data. I'm using the Basic Stamp editor v2.1, and it does not find the "Loop" or "Echo" when it is trying to connect to the stamp using the Aircable. I think I could program it if it didn't try to look for those two things before sending the program. Is there any way to turn those options off?

According to their website:

"The voltage levels are for RS232 devices:
about +5V for low and -5V for high.
The chip (MAX 3243/3238) cannot provide power to other
serial devices.
It also switches off (all level GND) when there
is no voltage on any of the input pins.
If you need to switch on the RS232 chip, just put
5V on DCD for example, that would switch it on."

But when I connect the Aircable to the stamp and turn the stamp power on, the voltage levels go to the correct value.

What can I do to be able to use the Aircable to program the stamp? It really works great for other serial devices, since it is small and has a pretty good range.

Thanks,
Dan

Comments

  • Jon WilliamsJon Williams Posts: 6,491
    edited 2004-11-07 06:14
    You may not get it to work. The BASIC Stamp editor does some bit-fiddling on the serial port to reset the module before reporgramming. All of this is timing sensitive and may not be passing through your connection.

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    Jon Williams
    Applications Engineer, Parallax
    Dallas Office
  • smoothswisssmoothswiss Posts: 4
    edited 2004-11-09 14:23
    But shouldn't the software still see the short between pins 6 and 7, or the loop? My BS2sx is on a Next Step board, so the short is built into the board.
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2004-11-09 14:28
    I don't know -- you might want to contact the Aircable folks to see if their adapter allows the sort of bit manipulation that the BASIC Stamp editor requires of the port.

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    Jon Williams
    Applications Engineer, Parallax
    Dallas Office
  • smoothswisssmoothswiss Posts: 4
    edited 2004-11-09 14:42
    Ya, I was posting questions on their forum before I found this one, so I'm corresponding between both now.

    What kind of bit manipulation is going on? I would like to explain this to them, so maybe they can let me know if it is possible.

    Also, have you used the "EmbeddedBlue Connect PC Adapter" to program a stamp wirelessly? I read in the forum that the data transmission delay is 11ms, which is about the same as the Aircable.

    Are there any other options to programming the stamp other than the Windows software I'm using that wouldn't do a serial port check?
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2004-11-09 16:18
    On our web site we make a document avaiable that explains our programming protocol and timing requirements. Look under Downloads >> BASIC Stamp Tokenizer

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    Jon Williams
    Applications Engineer, Parallax
    Dallas Office
  • Ken GraceyKen Gracey Posts: 7,400
    edited 2004-11-09 16:32
    Dan,

    Try setting the latency timer for the USB port to the lowest possible value it can be such as one. This solves some other problems I've had with other adapters (assuming the Aircable is USB). I couldn't tell for certain from your post if it is USB or serial on the PC side.

    Ken Gracey
    Parallax, Inc.
  • smoothswisssmoothswiss Posts: 4
    edited 2004-11-12 15:50
    Ken,
    It is USB on the PC side. It goes from a USB Aircable module on the PC to a serial Aircable module at the stamp.

    How do I set the latency timer for the USB port. I've never heard of this before, and I searched for instructions on the internet, but can't find any info. I'm using an IBM T40 Laptop, Windows XP SP2

    Thanks,
    Daniel
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2004-11-12 16:19
    Daniel,

    Follow this sequence to get to the Latency Timer:

    Start >> Control Panel >> System >> Hardware >> Device Manager

    Click on the [noparse][[/noparse]+] next to Ports to expand. Right click on the USB port that your adapter is connected to. On the Port Setting tab, click Advanced. Reduce the Latency Timer value to 1; we've seen this correct programming issues with USB adapters.

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    Jon Williams
    Applications Engineer, Parallax
    Dallas Office
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