PS1 Keyboard Interface      Don Carveth  July 2002

PS-2 (PC-AT) style keyboard interface.
Mirrors all characters typed on PC-AT keyboard on terminal connected to UART.

Based on Atmel App Note AVR-313
Converted supplied c code to GCC 3.2
Based on ATMEGA163 at 8 MHz

*********** REVISION HISTORY **************************
Rev 0   Creation        8/30/02
		Converted from IAR to GCC
		Operational.

*********** OPERATION *********************************
Connect PS-2 keyboard as shown below - see App note for connection info
Connect UART to terminal program at 19200 baud, 8N1
    
All standard keys pressed will mirror on terminal.  Shift works, <ctrl> and
<alt> have no effect.
Hit <F1> to alternate between character mode and hex code representation.


Connect an LED to PD5 to ensure the program is running.
Use the test pin at PB1 to monitor progress.  Insert test_pin() commands in
    the program to toggle the pin - watch on your scope. Only need
    for debugging.
    
To change processor or crystal make changes in StdDefs.h.
Select between polled and interrupt driven UART transmit (putchar) in StdDefs.h
	
*********** RESOURCES *********************************

Processor: ATMega163
Crystal: 4 MHz
Flash size: 0x7e6  (2022)
RAM Used: 0x9c  (156)
EEPROM Used: 0

Pins used:

PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7 

PB0 
PB1 
PB2 
PB3 
PB4  
PB5  MOSI   -  ISP, 
PB6  MISO   -  ISP,
PB7  SCK    -  ISP

PC0 
PC1 
PC2 
PC3 
PC4 
PC5 
PC6 
PC7 

PD0  UART Rcv
PD1  UART Txd
PD2  INT0  - Clock
PD3  INT1  - Data
PD4  
PD5  Run LED
PD6  
PD7  

Interrupts:
INT0 - PS-1 Keyboard clock

Timers: