Programming instructions

74xx
 National Instruments Corporation 6-35 Multisim Component Reference Guide
6.4.63 74xx191 (Sync 4-bit up/down Counter)
This device is a synchronous, 4-bit binary, reversible up/down counter.
6.4.64 74xx192 (Sync BCD Up/down Counter)
This device is a synchronous, BCD, reversible up/down counter.
Counter TC and RC truth
table:
INPUTS
TERMINAL COUNT
STATE
OUTPUTS
U
/D CE CP Q0 Q1 Q2 Q3 TC RC
11X111101
01X111111
00 11111
01X000001
11X000011
10 00001
1 = High voltage level
0 = Low voltage level
X = Don’t care
= Low pulse
ComponentRef.book Page 35 Thursday, December 7, 2006 10:12 AM