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Propeller demo board keeps reseting while connected with USB cable — Parallax Forums

Propeller demo board keeps reseting while connected with USB cable

AtleAtle Posts: 5
edited 2011-05-31 19:03 in Propeller 1
I'm using a Propeller demo board Rev F while testing the propeller chip.
The problem is that it keeps resetting about every 28 seconds while the USB cable is attached.
If the cable is removed it works fine.

Does anyone know if this is a known issue or is my demo board broken??

Comments

  • RaymanRayman Posts: 14,877
    edited 2011-05-31 05:54
    Their is a known problem when using "fullduplexserial" on pins 30&31, you can power up the USB chip and cause a reset...

    But, usually this happens when USB is not connected. So, you're problem seems backwards to that one...

    Anyway, if you are using serial I/O on P30&31, try turning that off...
  • Mike GreenMike Green Posts: 23,101
    edited 2011-05-31 07:36
    This problem occurs intermittently when using a USB to serial interface whenever I/O pin 30 is made high to attempt to transmit to the PC and no USB cable is plugged in. What happens is that the high on pin 30 provides enough power to the USB to serial interface chip so it tries to reset the Propeller (and usually succeeds). The Propeller resets and pin 30 stops being high until the program can be reloaded and restarted.

    The simplest solution is to check first for a possible USB connection ("if ina[ 31 ] == 1") before initializing whatever serial I/O driver you're using.
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2011-05-31 10:54
    Atle wrote: »
    I'm using a Propeller demo board Rev F while testing the propeller chip.
    The problem is that it keeps resetting about every 28 seconds while the USB cable is attached.
    If the cable is removed it works fine.

    This sounds the exact opposite of the "known" issue. If it happens when the USB cable is plugged in then you have some troubleshooting to do....

    - Do you have a USB cable directly connected between your PC and Protoboard or are you going through a USB Hub?

    - I would try a direct connection (if using a HUB) and perhaps a different USB cable.

    - What other USB devices do you have plugged in? If you have other USB devices connected then try to remove them to see if they are causing the reset issue. If a device is dropping off the USB BUS an being re-detected it may be resetting all the USB devices.

    - My Protoboard will reset whenever I plug in and connect any USB device. Perhaps an extra device is causing the issue or a driver on the PC.

    - What OS and version are you using? Is this a desktop or laptop? You may want to try adding a powered USB HUB in between your computer and the propeller board.

    Robert
  • AtleAtle Posts: 5
    edited 2011-05-31 13:19
    RobotWorkshop wrote: »

    - My Protoboard will reset whenever I plug in and connect any USB device. Perhaps an extra device is causing the issue or a driver on the PC.

    After doing some troubleshooting turning off all background programs I finally found that closing the "Sony Ericsson PC Companion" did the trick.
    I don't know exactly what this program does but it probably probes for a Sony Ericsson phones and this in turn makes the FTDI chip DTR line go
    low every 30 seconds.

    -Atle
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2011-05-31 13:39
    Thanks for posting which program was causing the problem and closing out the issue. If anyone else sees a similar problem then they can start checking what applications and drivers are on their PC.

    Robert
  • RaymanRayman Posts: 14,877
    edited 2011-05-31 18:37
    That is a strange one... I thought it sounded backwards...

    My Sharp 3D monitor does the same thing though (toggle DTR) to detect presense. It only does it once though...

    Kinda makes me wonder if the Sony Ericsson has an FTDI chip inside... Most newer serial implementations don't seem to use CTS or DTR...
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2011-05-31 19:03
    Rayman wrote: »
    Kinda makes me wonder if the Sony Ericsson has an FTDI chip inside... Most newer serial implementations don't seem to use CTS or DTR...

    It could be causing issues with other USB devices too. Either that or it is written to scan all Serial ports (real or USB based) that it sees on the system for it's own device.
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