adgal.pld

本代码可做为可编程逻辑器件ATF16V8B参考的例子

Name            Iodecode;
Partno          CA0010;
Revision        02;
Date            9/22/84;
Designer        zhy;
Company         Assisted Technology, Inc.;
Assembly        PC Multi-Function;
Location        U12;
Device          G16V8;

/************************************************************************/
/* This device generates the chip select signals for the I/O functions. */
/* It also enables the data bus transceiver for both memory and I/O     */
/* write cycles.                                                        */
/************************************************************************/

/** Inputs **/

pin 2 = a13;                  /* mcu addresses a13 - a15     */
pin 3 = a14;
pin 4 = a15;

pin 5 = aadrc;
pin 6 = aadcs;
pin 7 = aadce;


pin 8  	   = rd ;        /* mcu read         */
pin 9  	   = wr ;        /* mcu write         */

pin 1 	   = adsts ;     /* Status is Active HIGH when a conversion is in progress and goes LOW when the conversion is completed. */



/** Outputs **/

pin 19     = ads ;                     /* to 574 latch the ad dat  */

pin 18     = agco ;                    /* to latch agc control comand    */
pin 13     = adoeh ;                   /* 574 chip select   */
pin 12     = adoel ;                   /* 574 chip select   */

pin 15     = adcs ;
pin 16     = adrc ;
pin 17     = adce ;

/** Declarations and Intermediate Variable Definitions  **/


/** Logic Equations **/
ads    = !adsts ;

agco   = !(!wr & !a15 & !a14) ;

adoeh  = !(!rd & !a15 & a14 &  a13) ;

adoel  = !(!rd & !a15 & a14 & !a13) ;

adcs   = aadcs ;
adce   = aadce ;
adrc   = aadrc ;