Programming instructions

74xx

 National Instruments Corporation 6-39 Multisim Component Reference Guide

6.4.69 74xx199 (8-bit Shift Reg (sh/ld ctrl))

This device contains an 8-bit shift register with shift/load control.

Shift register truth table:

· = transition from low to high

a ... h = the level of steady state input at inputs A through H respectively

QA0, QB0, QG0,

QH0

= the level of QA, QB, QG, or QH, respectively, before the indicated steady state

input conditions were established

QAn, QBn, etc. = the level of QA, QB etc., respectively, before the most recent negative

transition of the clock

MODE SERIAL

PARALLEL OUTPUTS

CLEAR S/L CLKINH CLK J K A...H QA

QB..Q

0 X X XXXX 0 0 0

1 X 0 0 XXX QA0QB0QH0

1 0 0 · X X a...h a b..g h

1 1 0 · 01X QA0QA0QGn

1 1 0 · 00X 0 QAnQGn

1 1 0 · 11X 1 QCn1

1 1 0 · 10X

QAn QAn QGn

1 X 1 · XXX QA0QB0QH0

· = transition from low level to high level