I2C Bus interface GAL logic equations file
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Name     I2C_01 ;
PartNo   00 ;
Date     19/03/01 ;
Revision 01 ;
Designer Lee ;
Company   ;
Assembly None ;
Location  ;
Device   g16v8as ;

/* This GAL is the select logic for the I2C interface board	*/

/* Logic minimisations			None			*/
/* Optimisations			None			*/
/* Download				JEDEC/POF/PRG		*/
/* Doc File Options			fuse plot, equations	*/
/* Output				None			*/

/* *************** INPUT PINS *********************/

PIN	1 = A4		;			/* address bus		*/ 
PIN	2 = A3		;			/* address bus		*/ 
PIN	3 = A2		;			/* address bus		*/ 
PIN	4 = A0		;			/* address bus		*/ 
PIN	5 = A1		;			/* address bus		*/ 
PIN	6 = p02		;			/* CPU phase 2		*/ 
PIN	7 = RW		;			/* read write		*/ 
PIN	8 = !SEL1	;			/* block select		*/ 
PIN	9 = !SEL0	;			/* block select		*/ 
PIN	11 = A6		;			/* address bus		*/ 
PIN	12 = A5		;			/* address bus		*/ 
PIN	13 = A7		;			/* address bus		*/ 

/* *************** OUTPUT PINS *********************/

PIN  19 = !KBR		;			/* key port read strobe		*/ 
PIN  18 = !KBW		;			/* key port write strobe	*/ 
/*PIN  17 = 		;			/* 				*/ 
/*PIN  16 = 		;			/* 				*/ 
/*PIN  15 = 		;			/* 				*/ 
/*PIN  14 = 		;			/* 				*/ 

/* intermediate terms */

ADDR		= !A7 & !A6 & A5 & !A4 & !A3 & !A2 & !A1 & A0 & !SEL0 & SEL1 ;
							/* F121h (0010 0001)

/* Output terms */

KBR	= ADDR &  RW & p02 ;			/* key port read strobe		*/
KBW	= ADDR & !RW & p02 ;			/* key port write strobe	*/

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