Programming instructions

74xx
 National Instruments Corporation 6-31 Multisim Component Reference Guide
Parity generator/checker truth table:
6.4.60 74xx181 (Alu/Function Generator)
ALU/function generator truth table:
INPUTS OUTPUTS
S OF H’s AT A
THRU H
EVEN ODD
S
EVEN
S
ODD
Even 1 0 1 0
Odd 1 0 0 1
Even 0 1 0 1
Odd 0 1 1 0
X1100
X0011
ACTIVE - LOW DATA
SELECTION M=H M=L; ARITHMETIC OPERATIONS
S3 S2 S1 S0
LOGIC
FUNCTIONS
Cn=L
(NO CARRY)
Cn=H
(WITH CARRY)
0000F=A
F= A MINUS 1 F= A
0001F= AB
F= AB MINUS 1 F= AB
0010F= A+B
F= AB MINUS 1 F= AB
0 0 1 1 F= 1 F= MINUS 1(2's comp) F= Zero
0100F= A+B
F= A PLUS (A+B) F= A PLUS(A+B) Plus 1
0101F= B
F= AB PLUS(A+B) F= AB PLUS (A+B) PLUS 1
0110F= A“+”B
F= A MINUS B MINUS 1 F= A MINUS
0111F= A+B
F= A+B F= (A+B)PLUS1
1000F= A
B F= A PLUS (A+B) F= A PLUS (A+B) PLUS 1
1001F= A“+”B
F= A PLUS B F= A PLUS B PLUS
1010F= B F= AB
PLUS(A+B) F= AB PLUS (A+B) PLUS 1
1 0 1 1 F= A + B F= (A + B) F= (A+B) PLUS 1
ComponentRef.book Page 31 Thursday, December 7, 2006 10:12 AM