Hello! I'm pretty new to Arduino, but I'd like to be able to use an RFID module to unlock my computer. I've looked at the topic of UNO keystrokes, and found some information, but it seems like there is some conflict on the info. I'd like to get a definitive answer to this question...
Here's some of the stuff I've seen.
1: UNOs cannot write keystrokes.
2: Clone UNOs have different chips.
3: UNOs CAN write keystrokes with a new driver update (or something like that).
Can I write keystrokes from my UNO clone? It is from the Elegoo "The Most Complete Starter Kit." I've seen somewhere that clones can have different chips, but I don't know what chip the Elegoo UNO uses. I've also seen that with a new driver update, or something, that UNO boards can now make keystrokes. Will this download be compatible with my Elegoo UNO and chip? If not, is there any beginner friendly way to have my board write keystrokes other than buying a different board?
Thanks!!!
What do you mean "make keystrokes"? If you mean Keyboard Emulator, it appears that the keyboard library only works on the Leonardo, Esplora, Zero, Due and MKR Family.
And also the Micro.
Yes you can use the Uno to do this but once you do you have to go through a long rigmarole in order to program it again. So the development cycle is messy.
Clones can have anything in them. Best avoid them as a beginner and go for real boards.
Where "writing keystrokes" refers to appearing as a HID device such as a keyboard or mouse, an actual UNO will not be able to do this "out of the box". However the USB interface chip on a real UNO, the 16U2 can be re-programmed via its own ICSP header to do this. As Mike says, there is a bit of work involved; you need the code to do it and you need an ICSP programmer (such as another Arduino).
tyster02:
2: Clone UNOs have different chips.
Many clones offered as "UNO"s are not actually UNOs at all. A UNO is defined by the 16U2 (earlier: 8U2) USB interface chip. If it does not have this, is is not a UNO at all, but a clone of the earlier Duemilanove design, and obviously cannot be used as a HID device.
tyster02:
3: UNOs CAN write keystrokes with a new driver update (or something like that).
As explained if it is a genuine UNO design, not a mendaciously advertised fake. Many clone manufacturers actually do make real UNO clones with the genuine 16U2 but these will be more expensive. Most fakes now use the Chinese-designed CH340 USB-to-serial chip.
I forget what the name of the alternative 16U2 software is - someone will no doubt explain - but it is a whole lot easier and more practical to use a Pro Micro if you need an HID emulation.
The firmware for the Micro and Leonardo came from Arduino-compatible makers PJRC.com who had the Teensy line out when you couldn't get the Leo or Micro.
They're team players, not ripoffs or knockoffs, so perhaps include the Teensy 2 and Teensy++ 2 USB-AVR boards and the Teensy 3's and 4 ARM chip Franken-boards.
I dunno but I bet team players Adafruit and Sparkfun to name just two also have USB-AVR and ARM boards as well.
The USB-AVR chip boards make HID pretty easy though for beginners substitute "possible" for "easy". They do it with hobbyist-friendly-more-robust-than-ARM AVR pins.
There is a much harder route from before the USB-AVR boards showed up, you can run the V-USB library on a standalone AVR, it even works on ATtiny85's!