Microcontroller:
- ATmega16 (32 IO-Pins)
- available IO pins:
	- PA0-7
	- PB0-7 (including PB5-7 for ISP)
	- PC0-7
	- PD2-7 (PD0 and PD1 are UART pins)

EEPROM:
- Atmel AT28C256
- IO and control pins:
	- 8 data lines (I/O) D0-7
	- 15 address lines A0-14
	- inverted Chip Enable ~CE
	- inverted Output Enable ~OE
	- inverted Write Enable ~WE

Usage
-----
- 1 microcontroller (µC), 1 EEPROM
- direct parallel data IO

Pin allocation
--------------
- on µC
	- PC0-7 --> EEPROM address lines A0-7
	- PB0-6 --> EEPROM address lines A8-14
	- PA0-7 <-> EEPROM data lines D0-7
	- PD0-1 <-> UART TX/RX
	- PD2   --> EEPROM ~CE
	- PD3   --> EEPROM ~OE
	- PD4   --> EEPROM ~WE

- on EEPROM
	(see µC)


Reading process
---------------
1. reset EEPROM control bits to [chip disabled, output disabled, write disabled]
	PORTD2..4 = 111
2. set data pins as inputs (without pullups - maybe disable pullups at all (PUD in SFIOR))
	DDA0..7   = 00000000
	PORTA0..7 = 00000000
3. set address
	PORTC0..7 = [Address bits 0..7]
	PORTB0..6 = [Address bits 0..6]
4. set EEPROM to read mode by enabling chip and output [chip enabled, output enabled, write disabled]
	PORTD2..4 = 001
5. wait ~150ns
6. read byte from data pins
	DATABYTE0..7 = PINA0..7
7. reset control bits
	PORTD2..4 = 111
8. to read next byte, continue at step 3.


Writing process
---------------
1. reset EEPROM control bits (see reading)
	PORTD2..4 = 111
2. set data pins as outputs (and reset output pins)
	DDA0..7   = 11111111
	PORTA0..7 = 00000000
3. set address
	PORTC0..7 = [Address bits 0..7]
	PORTB0..6 = [Address bits 0..6]
4. set control bits to latch address (falling edge)
	PORTD2..4 = 010
5. set data output to the value to be written
	PORTA0..7 = WRITEBYTE0..7
6. wait 50ns (data setup time)
7. set control bits to latch data and start write cycle (rising edge)
	PORTD2..4 = 111
8. wait 50ns (pulse width)
9. WAIT UNTIL WRITING IS FINISHED
	(we can poll D7 to check if write cycle is finished - do we want to do that?)
10. to write next byte, continue at step 3.


Page writing
------------
/* TODO */