Comments: Programming the pcDuino


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  • Member #571263 / about 9 years ago / 1

    I try to test python code to PCduino V2 with MAX7219. To let 4-digit 7 segment present a counter number using SPI communication.

    I connect wire from MAX7219 to PCduino:

    cs to pin 10(digital I/O) clk to pin 13(clk) Din to pin 11(MOSI)

    This below is a source code.

    import spi import time import gpio

    cspin = "gpio10"

    def maxsend(address, value): gpio.digitalWrite(cspin, gpio.LOW) spi.transfer(address) spi.transfer(value) gpio.digitalWrite(cspin, gpio.HIGH)

    def setup(): gpio.pinMode("gpio13", gpio.OUTPUT) gpio.pinMode("gpio11", gpio.OUTPUT) gpio.pinMode(cspin, gpio.OUTPUT) gpio.digitalWrite(cspin, gpio.HIGH) spi.openSPI(speed=1000000, mode=0) time.sleep(0.01) maxsend(0x0B, 0x06) maxsend(0x09, 0xFF) maxsend(0x0A, 0xFF) maxsend(0x0C, 0x01) maxsend(0x0A, 0x0F)

    def loop(): for i in range(0,2000): maxsend(0x04,i%10) maxsend(0x03,(i/10)%10) maxsend(0x02,(i/100)%10) maxsend(0x01,(i/1000)%10) time.sleep(0.5)

    setup() loop()

    When I run it, nothing happen on 7 segment But it has a message show on terminal:

    Only accepts a single tuple as an argument
    Success Aborted

  • Member #90923 / about 9 years ago / 1

    Device Tree Overlays, does pcDuino require/use them? Or has that been taken care of in the image and the auto load of an appropriate DTO on boot?

  • Member #536770 / about 9 years ago / 1

    I have the same problem... I need an answer it is really hurry for me!! ... amm.. i just get this ... .

    fd = open(file, ‘r’) IOError: [Errno 2] No such file or directory: ‘/sys/class/leds/pwm0/max_brightness

    Please HELP!!

  • judlup / about 9 years ago / 1

    Good day! I'm trying to use the nrf24l01p with pcduino, but i don't found a library for this, who can help me? I will be grateful

  • Member #413976 / about 9 years ago / 1

    When I try to save the HelloWorld file, I get an error "Can't open file to write". This happens even when just trying to create a folder. Any ideas?

  • Member #278404 / about 9 years ago / 1

    I can't seem to get the serial (/dev/ttyS1) to work on my pcduino. My goal is to connect it to a sabertooth motor controller.

    I would think I should be able to connect the RX/TX pins and then screen /dev/ttyS1 9600 and be able to type and see what I type, but I can't.

    I also ran the python script included in the Serial Communication section and I just get "You typed " and return to prompt.

    I suspect its because I need to set the pin to mode 3, but I wasn't clear on how to do that from the tutorial. Is there a way to do this from the command line?

  • gumush / about 10 years ago / 1

    I copied all scripts from Github , GPIO worked correctly. But didn't worked.

    It returned "No such file or directory: ‘/sys/class/leds/pwm0/max_brightness’"

    ls -la /sys/class/leds/ returns nothing , folder empty.

    Is there any other things needs to be installed ?

  • Member #460867 / about 10 years ago * / 1

    I encountered the same problem..... neigher C++ nor Python works.....

    • Soshimo / about 10 years ago * / 1

      I just read the entire article - doh - and I noticed the link to the github repo. Check it out. Once I cloned the repo everything built and ran fine.

      • TomasG / about 9 years ago / 1

        i have cloned this repo using latest images and kernel from but doesn't have anything in sys/class/leds

  • Macro / about 10 years ago / 1

    Exactly the same here!

  • Member #220425 / about 10 years ago * / 1

    I have entered simple analog input and output program, and i been keep facing error saying:

    Traceback (most recent call last): File "", line 43, in fd = open(file, 'r') IOError: [Errno 2] No such file or directory: '/sys/class/leds/pwm0/max_brightness'

    code is python code(

    What am I doing wrong?

    OS info: Linaro 12.07 (GNU/LINUX 3.4.29+ arm71)

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