PAL14L8                                          PAL DESIGN SPECIFICATION
U1                                                   Bob Metzler 12/30/90
DUAL 4:1 MULTIPLEXER
MYTEST REDMOND,WASHINGTON
A1 B1 C1 D1 X1 NC X2 A2 B2 C2 D2 GND
NC NC Y2 NC NC NC NC NC NC Y1 NC VCC
;pinlist 1 to 24 must start in line 5

;equations go here

/Y1 = /X1*/X2 * /A1
    + /X1* X2 * /B1
    +  X1*/X2 * /C1
    +  X1* X2 * /D1

/Y2 = /X1*/X2 * /A2
    + /X1* X2 * /B2
    +  X1*/X2 * /C2
    +  X1* X2 * /D2

; function table vectors go here

FUNCTION TABLE
D1 C1 B1 A1 D2 C2 B2 A2 X2 X1 Y1 Y2

;function table pin list
;     INPUTS         CONTROL   OUTPUTS
; D C B A   D C B A   X X      Y  Y
; 1 1 1 1   2 2 2 2   2 1      1  2
---------------------------------------------------------
;check for high outputs
  H H H H   H H H H   L L      H  H
  H H H H   H H H H   H L      H  H
  H H H H   H H H H   L H      H  H
  H H H H   H H H H   H H      H  H
;check for low outputs on Y1
  H H H L   H H H H   L L      L  H
  H H L H   H H H H   H L      L  H
  H L H H   H H H H   L H      L  H
  L H H H   H H H H   H H      L  H
;check for low outputs on Y2
  H H H H   H H H L   L L      H  L
  H H H H   H H L H   H L      H  L
  H H H H   H L H H   L H      H  L
  H H H H   L H H H   H H      H  L
---------------------------------------------------------
DESCRIPTION
This example uses a PAL14L8 as a dual 4:1 multiplexer. The select lines
(X1,X2) along with one of the 4 inputs (A,B,C,D) will drive the output
(Y) low. If no inputs are low the outputs are high.