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*   FILE: I2C Demo        
*
*   DESC: I2C data transfer between AVR(or any I2C device) and TI92+.
*    	  	     
*                          
* AUTHOR: Zoltan Gradwohl 
*   DATA: 05/29/05
*  EMAIL: zgrad@web.de
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Overview:
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The Ti92+ sends a byte over the I2C (TWI) network to the Atmega8. To confirm the transmission
the Atmega8 imediately sends the received byte over a RS232 link to a PC. After a small delay 
the TI calls the Atmega8 again and sends the read bit together with the slave address. After 
that the Atmega8 sends the previously received data back to the TI. Because the TI awaits two
bytes the Atmega8 transmits the received data back to the TI twice (only for testing purposes).


DISCLAIMER:  Any connections you make involving your calculator and your computer/other device
DISCLAIMER:  are done at your own risk.  I take no responsibility for damaged items.


Keys:
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RIGHT:  Transmit 0x02 to slave 
LEFT:   Transmit 0x01 to slave 
UP:     Transmit 0x03 to slave 
DOWN:   Transmit 0x04 to slave 

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F2:     decrease slave device address
F1:     increase slave device address

ESC: 	Exit programm