34 lines
760 B
Plaintext
34 lines
760 B
Plaintext
ASCII to USB keyboard protocol converter
|
|
========================================
|
|
This converts serial console terminal into USB keyboard, tested with TRS-80 model 100 TELCOM application.
|
|
Target MCU is ATMega32u4 but other USB capable AVR will also work.
|
|
|
|
|
|
Hardware
|
|
--------
|
|
Connect RX, TX and GND to UART pin of AVR. Note that you may need line drvier/level shfiter like MAX232 to interface high voltage of RS-232C.
|
|
|
|
|
|
|
|
Build Firmware
|
|
--------------
|
|
Configure UART setting and Just use 'make'
|
|
|
|
$ cd ascii_usb
|
|
$ make
|
|
|
|
Then, load the binary to MCU with your favorite programmer.
|
|
|
|
|
|
|
|
Limitation
|
|
----------
|
|
- This cannot see key up event, you cannot hold a key.
|
|
- Alt, Gui(Win/Mac) modifier key are not available.
|
|
|
|
|
|
|
|
Scan code
|
|
---------
|
|
ASCII code(0x01-7F)
|