PS/2 to USB keyboard converter ============================== This firmware converts PS/2 keyboard protocol to USB and supports only Scan Code Set 2. PS/2 signal handling implementations ------------------------------------ Following three methods are used to implement PS/2 signal handling. ### Simple and stupid busy-wait(ps2_busywait.c) This is expected to implemented with portable C code for reference. ### Interrupt driven(ps2_interrupt.c) Uses pin interrupt to detect falling edge of clock line. ### USART hardware module(ps2_usart.c) Uses AVR USART engine to recevie PS/2 signal. To select method edit Makefile. Connect Wires ------------- In case of Teensy2.0(ATMega32U4): 1. Connect Vcc and GND. 2. Connect Clock and Data line. - Busywait: Clock is on PD5 and Data on PD2. - Interrupt: Clock is on PD1 and Data on PD2. - USART: Clock is on PD5 and Data on PD2. 3. Optionally you need pull-up register. 1K-10K Ohm is OK. To change pin configuration edit config.h. Build Frimware -------------- Just run `make`: $ make To select keymap: $ make KEYMAP=[plain|jis|spacefn|...] Keymap ------ Several version of keymap are available in advance but you are recommended to define your favorite layout yourself. To define your own keymap create file named `keymap_.c` and see keymap document(you can find in top README.md) and existent keymap files. V-USB Support ------------- You can also use this converter on ATmega(168/328) with V-USB instead of Teensy. The converter on V-USB lacks some features for now: USB NKRO and System/Media control. Circuit: +---+ +---------------+ USB GND | | ATmega168 | === C3 | | 5V <-------+--------+---|Vcc,AVCC | PS/2 R1 | | ==== D- <----+--+-----R2-----|INT1 RXD|------->DATA D+ <----|---+----R3-----|INT0 XCK|------->CLOCK Z1 Z2 | | ->5V GND<----+---+--+--+-----|GND | ->GND | | | | | C2-+--|XTAL1 | | X1 | | +--C3-+--|XTAL2 | +---------------+ R1: 1.5K Ohm R2,R3: 68 Ohm Z1,Z2: Zenner 3.6V C1,C2: 22pF C3: 0.1uF X1: Crystal 20MHz(16MHz/12MHz)