CHPA SERIES
3-12
THIS
DOCUMENT
IS
THE
PROPERTY
OF
COMMUNICATIONS
&
POWER
INDUSTRIES.
REPRODUCTION
OR
RELEASE
WITHOUT
EXPRESS
PERMISSION
IS
STRICTLY
PROHIBITED
D
OC
.01023245
R
EV
.L
Table 3-6. Reject Bytes (continued)
ASCII Character
Decimal
Meaning
d
100
Slow command in execution
f
102
The command was not executed; high voltage is OFF.
g
103
The command was not executed; RF is inhibited.
i
105
The command was not accepted; unit is in Fault.
3.9.6 Check
Byte
(Check byte is under CIF CONFIGURATION as CHECKBYTE.)
Two options are available:
Longitudinal Parity—The check byte is the exclusive OR of all message bytes including the
header and ending bytes and excluding CR or LF if chosen. (LONG on front panel.)
Checksum—This formula provides a printable ASCII checksum. (SUM on front panel.)
N
Checksum = 32 + MOD
95
[(
Σ
message byte
i
) – (32 * N)]
i=1
where:
•
MOD
95
is the operation modulo 95.
•
N is the total number of bytes in the message including header and ending bytes and
excluding CR or LF if chosen.
•
message byte
i
is the ith message byte where 1
≤
i
≤
N.
Example: Calculate the check byte for the message {A1} using the checksum rule.
Character: { A 1 }
ASCII: 123 65 49 125
i: 1 2 3 4
Check Byte = 32 + MOD
95
[(123+65+49+125) – (32*4)]
= 32 + MOD
95
[234]
= 32 + 44
= 76 which translates to the ASCII character L
