Campbell 21X Operator's Manual page 173

T2
=
shift left (Ss(n)) + carry
4.
Form
the new low signature byte by adding
the results of operation 3 to
the old high
signaturE byte and the
transmitted byte.
lgnore
arpy
carry bits resulting from these
add opergtions.
Se(rf+1)
=Tz* 51(n)
+ M(n+1)
As
each new transmitted byte
is.
received, the
procedure
is pepeated.
APPENDIX
C.
BINARY TELECOMMUNICATIONS
lr
|
,r
=
Sr(n)
I
S1(n+1)=
So(n)
t''
I
3.
Form
a
tpmporary byte by shifting the old
low
sign{ture byte one bit to the left and
adding
afy
carry bit
which results from the
shift
opefation. A "shift left" is identicalto a
multiply $y
2.
lgnore any carry
bit resulting
from the
hdd.
c-5