ARCELI USB Host Shield Support Google Android ADK USB HUB

This shield uses the 74hc125 to accomplish logic level shifting. The 74hc125 is not the correct device to translate from 5v to 3.3v. if you find your self beating your head against the wall measure your voltage on the 3.3v pin. If it is greater than 3.3v then the max3421 will not detect most devices.

My objective was simply to use a very inexpensive (<$20) Logitech USB Keyboard as a "remote control" of one MAX7219 board with 64 LEDs (8x8 matrix) on an Arduino UNO - 5v at about 3mA per LED at max intensity of "15." This could easily be made to control 256 LEDs with 4 x 7219's, right? I have not tried that yet. Range is over 30 feet - never tested longest range; whatever max wireless keyboard capability is. HOWEVER, there were a couple curious QUIRKS I have yet to work out. Seems I MUST POWER the combo of UNO/HOST SHLD from the UNO USB from a PC or a power cube in an outlet; will typically not work using only DC Power Input Socket on UNO - i.e. will not work dependably with no power to the USB port... it tries to... and will sometimes if it WAS just powered from the USB and unplug it with power to the VDC port, but will not initiate on reset with DC power alone. I've tried fooling the UNO USB port into thinking it was powered from a cube... injecting 5v/3.3v to the USB, but that is not working just yet. I've scoured the schematics of both UNO and HOST SHLD, but still confused what is special about the USB power on the UNO versus the 5 VDC input power - appear to be the same difference. Also, HOST SHLD is supposed to pass I/O through but digital pins that worked to control 7219 from the UNO alone, no longer worked out of the HOST SHLD header. I moved them to A0, A1 & A2, (as shown in the photo) and it works fine. Still have to investigate what happened to those digital I/O. ALSO, there are MANY online videos about using this HOST SHLD card and the 7219, but I found I had to watch quite a few to get all the info I needed to make this work as I wanted - any single ASCII keyboard code can be assigned to any single LED - and that's all I was after. Thanks for reading!

You have to solder it before. If done properly, it will work flawlessly and pass all quality checks.

No Complaints, pins came slightly bent, but it was an easy adjustment

Het product werkt goed na wat aanpassingen aan het bord. Je moet de punten op de afbeelding bridgen met soldeertin om dit bordje te laten werken op een Arduino Uno. - Je ziet 3 groen gemarkeerde punten op de afbeelding - Elk van deze punten heeft 2 soldeerbolletjes, deze verbind je met elkaar door wat tin toe te voegen zodat ze in elkaar overlopen.