[Solved] pinout - CardKB programming via ISP



  • Hi,

    I tried to fiddle with the CardKB mega328p chip, but have troubles connecting it to the programmer, as below:

    $ avrdude  -c usbasp -p atmega328p
    
    avrdude: error: program enable: target doesn't answer. 1
    avrdude: initialization failed, rc=-1
             Double check connections and try again, or use -F to override
             this check.
    
    
    avrdude done.  Thank you.
    

    The pinout I inferred is also below (leftmost square hole for MISO, then Vcc, SCK, MOSI, RESET and Ground). the black thing on the wires is conductive paint I use as temporary solder, hasn't failed me yet ;)
    0_1568457206504_pins isp cardkb.jpg

    My question is whether the pins are connected in the right order, as I could not find any official pinout except for the photo on AliExpress which indicated it is an ISP connector on the bottom of the keyboard.

    If yes, I'll try soldering and changing kables or programmers to double check. I just don't have any idea if adding resistor or anything else could help in this case. Thanks for help.

    EDIT: I also tried connecting the GND pin to all possible pins on the programmer. Also tried slow / power jumpers on and off.

    Also, when I run AVRdude, the rgb led on the keyboard blinks shortly.



  • @ptrm said in CardKB programming via ISP:

    CardKB

    https://docs.m5stack.com/#/en/unit/cardkb
    Mega328 ISPDownload interface Pin foot definition
    0_1568599238551_mega328_isp.png



  • Yay, been on the docs subdomain, missed this one. Thanks :)

    ~  avrdude -c usbasp -p atmega328p
    
    avrdude: AVR device initialized and ready to accept instructions
    
    Reading | ################################################## | 100% 0.00s
    
    avrdude: Device signature = 0x1e950f (probably m328p)
    
    avrdude: safemode: Fuses OK (E:F9, H:D8, L:C2)
    
    avrdude done.  Thank you.