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Propeller Professional Development Board not responding — Parallax Forums

Propeller Professional Development Board not responding

DavidZemonDavidZemon Posts: 2,973
in Propeller 1
My PPDB is plugged into a 12V wall wart and nothing else. I flip the power switch and the "ON" LED blinkys at approximately 1 Hz. If I connect the board to my computer, lsusb lists the FTDI chip, but propeller-load fails to program:
david@balrog:~/stuff$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 016: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC
Bus 001 Device 005: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 001 Device 004: ID 046d:0826 Logitech, Inc. HD Webcam C525
Bus 001 Device 002: ID 0424:2514 Standard Microsystems Corp. USB 2.0 Hub
Bus 001 Device 011: ID 0925:3881 Lakeview Research Saleae Logic
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
david@balrog:~/stuff$ /opt/parallax/bin/propeller-load -bactivityboard ~/stuff/MCP2515_Demo -r -t
Ignored 253 bytes. 
Ignored 253 bytes. 
error: can't find a port with a propeller chip

Is my PPDB busted? Maybe the wall wart?

Comments

  • DavidZemonDavidZemon Posts: 2,973
    If I send 5V directly to the 5V terminal, it works correctly.
  • MikeDYurMikeDYur Posts: 2,176
    Oh! David, Hopefully it's that noisey wall-wart, my heart goes out to you if not.
  • twm47099twm47099 Posts: 867
    When I plug mine into a 5 cell AA battery pack (7.5v), the power on LED glows steady, no blinking.

    Tom
  • pmrobertpmrobert Posts: 673
    I killed the 12v-5v regulator on mine by an inadvertent short between +5v and gnd, same symptoms as you've experienced. I did as you've already done (power the +5 directly) for a while but did eventually replace the smoked regulator with full resolution of all signs of the malfunction. I do hope, also, that a crappy wall wart is the source of your trouble.

    Mike R....
  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2016-06-25 13:51
    It's a pity that they insist on using linear regulators instead of switch-mode when powered from 12V. Even at modest currents the regulator is going to be stressed and especially will it be stressed when you start hooking up the LED displays and other loads. As Scottie would say "I dannae is she can take any more"

    So occasionally you should not be surprised if the reactor goes critical.

    BTW, the use of the word "professional" is inappropriate for even this reason alone, "educational" perhaps.
  • evanhevanh Posts: 15,916
    The 1Hz blinking is probably the 12 volt switch-mode in the wall wart repeatedly restarting after over-current condition. The linear regulator would indeed be a candidate for this but be aware there is no end to the possibilities for cause of short circuits.
  • DavidZemonDavidZemon Posts: 2,973
    Thanks all. So it's the big chip labeled "5V" between the on/off switch and the FTDI chip right? Anyone have suggestions for replacement part number? I don't mind making an attempt to resolder it. The 3.3V chip must be working still since the Propeller runs okay with 5V applied to the 5V terminal?
  • Peter JakackiPeter Jakacki Posts: 10,193
    Do yourself a favor and graft in one of these little switchers, they're cheap but won't stress. You can run them at up to 24V input with 5V @0.5A and not even break a sweat. Less than $3 one off.
  • D.PD.P Posts: 790
    I've accidentally popped my 5 volt reg. The short even cause me to replace the prop chip but the board is still good. The board is tuff, I've got two little 1.5A switchers to rework into my board but until then I have put fuses between the 3.3 / 5 V output blocks and the breadboard.
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