johnc

Member Since: December 12, 2008

Country: United States

  • Product SEN-09695 | about a year ago

    Jimbo, thanks so much.. in the 5 days since I asked I’ve become (I think) a convert to Fritzing.. would you or anyone happen to have a library model for the MPR121 breakout board already done up in Fritzing ? The new library editor in Fritzing is not yet complete.. and there doesn’t seem to be a good way to import from eagle.. Any pointers appreciated. Thanks ! -jc

  • Product SEN-09695 | about a year ago

    Would you guys be willing to share the eagle files for this breakout board ? Thanks ! -jc

  • Product SEN-09695 | about 2 years ago

    Folks, I’m using an MPR121 + arduino in a musical device and its working quite well. I’m doing trial and error changes on the settings for touch and release thresholds, auto calibration modes and debounce settings. I have it working pretty well, but I’m now trying to do some final tuning in which I’m trying to balance touch sensitivity to noise sensitivity and latency. I’ve read the MPR121 tutorials.. but still am struggling a bit. While I’m successfully writing the config registers, I can also read the key press register (0x5A) One thing I have not figured out how to do is to read the other internal register values (eg. the raw sense value, the current baseline, etc ) on the device and print them to the serial monitor in the Arduino. I’ve tried using the same scheme to do an I2C read for other registers.. but they always come back 0’s. Does anyone have a code fragment that shows how to read these register values.. ? Also.. does anyone have any suggestions on a process to optimize the the touch/release thresholds for a specific configuration ? Ive tried to work things out from the mfg tutorial at http://cache.freescale.com/files/sensors/doc/app_note/AN3889.pdf but its a little academic..
    Any help / guidance on this would be much appreciated. Thanks ! -jc

  • Product DEV-09947 | about 3 years ago

    Hi folks.. I have one of your usb host shields. I’ve been trying to use it with a 328-based duemilinova and Oleg’s code (Thanks Oleg).. but I’ve not been able to get it to successfully talk to anything. I’ve tried a samsung tracphone, a moto v220 a blackberry 9630, a moto droid 2 and a canon powershot camera.. Neither Oleg’s acm_terminal or hub_demo packages can connect.
    When I try Oleg’s board_qc I get the following report
    Circuits At Home 2011
    USB Host Shield Quality Control Routine
    Reading REVISION register… Die revision 03
    SPI long test. Transfers 1MB of data. Each dot is 64K……………. SPI long test passed
    GPIO test. Connect GPIN0 to GPOUT7, GPIN1 to GPOUT6, and so on
    Test failed. Value written: 00 Value read: FF
    Press any key to continue…
    GPIO test passed.
    PLL test. 100 chip resets will be performed
    Resetting oscillator
    Reset number 0 Time to stabilize – 689 cycles
    Reset number 1 Time to stabilize – 691 cycles
    … (deleted for brevity)
    Reset number 99 Time to stabilize – 689 cycles
    Reset number 100 Time to stabilize – 691 cycles
    Checking USB device communication.
    Waiting for device …
    Waiting for device …
    … (deleted for brevity)
    it never connects.. no matter what device I plug into the host usb port
    Note there’s a test failure in the gpio section
    So.. my questions:
    * First, is it reasonable to assume that Oleg’s board_qc routine should work on your version ?
    * second.. could this be related to the GPX/RESET problem mentioned above ? If so.. I can’t figure out from the commentary whether there’s a HW fix for that .. or a sw fix.. or both.. can someone point me at an explanation ?
    * Finally.. is it possible thta the board is bad ? If so.. how would I return it for replacement
    Thanks so much for your help.. and sorry for the longish note
    -jc

  • News - Free Day is Done | about 4 years ago

    Guys…
    I think FREE Day is such a wonderful idea.. It’s such a cool and generous way to support the hacking community… So thanks you for that..
    That said.. I tried dutifully from the opening bell at 9MST to the closing bell just to finish my checkout on my $75, 3 item order .. and your server kept timing out. I was so excited when it finally came through only to find that 1the 100K had been reached.. I guess you know this.. but your servers wern’t up to your generosity :-)
    Again.. my admiration for what you did here more than offsets my frustration and disappointment that mine didn’t get through. Thanks for thall us geeks !
    -john c

  • Product COM-09259 | about 4 years ago

    I was wondering if i could use this shield to switch low wattage AC to power something like LED xmas lights.. or low wattage 110VAC incandescents. Looking at the schematic it looks like the triacs could handle it.. is there any reason this wouldn’t work ? I understand the pc leads might not be up to much current. Thanks !
    -jc

No public wish lists :(