Bit Shift Registers
Chapter 20
20-5
The Bit Shift Right output instruction constructs a synchronous bit shift
register from 1 to 999 bits in length. Figure 20.4 shows a 128 bit register
starting and ending at words 400 and 407.
Figure 20.4
How the Processor Shifts a Bit to the Right
16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
R
R
32
17
R
R
48
33
R
R
64
49
R
R
80
65
R
R
96
81
R
R
112
97
R
R
128
113
R
127
123
66
67
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
Bit Address
Input Bit B
Word Address
Output Bit A
Bit one of
Bit Shift Register
400
401
402
403
404
405
406
407
10387-I
Bit Shift Right