CPI Satcom Division VZC-6967 Series, Installation, Operation And Maintenance Manual

Page: 51 / 140

CHPA SERIES
D
OC
.01023245 R
EV
.L
THIS DOCUMENT IS THE PROPERTY OF COMMUNICATIONS & POWER INDUSTRIES.
REPRODUCTION OR RELEASE WITHOUT EXPRESS PERMISSION IS STRICTLY PROHIBITED
3-17
3.11 Status Byte Definitions
Status bytes are the responses to Query commands. Each bit represents some piece of
information; the bit definitions are provided in Tables 3-11 to 3-14. Bit 0 corresponds to the least
significant bit (LSB) and bit 7 corresponds to the most significant bit (MSB). Bit 7 will contain
the parity bit, if chosen. To make all status bytes printable ASCII characters, bit 6 is always
equal to the complement of bit 5.
Table 3-11. Summary Status Bytes
Byte Bit Bit Definition
7(MSB) Parity
6 Complement of bit 5
5 Change bit . This bit is set if the current power level differs by more than 0.1 dB from the
value returned by the last successful RF power query. This bit is zero if RF is inhibited
or if the CHPA is in Standby. The value of this bit is determined each time a Summary
Status Query is requested.
4 Info/Error Message Data Check . This bit is set when a selected information or error
condition has occurred. This bit is cleared by an Info/Error Message Query command.
Refer to Interface commands, Activate Info/Error Message command, and Deactivate
Info/Error Message command.
3 Secondary Status Data Check . This bit is set when any change in a Secondary Status
byte occurs. This bit is cleared by a Secondary Status Query.
2 Fault/Misc Status Data Check . This bit is set when any change in a Fault/Misc status
byte occurs. This bit is cleared by a Fault/Misc Status Query.
1 ALC active . This bit is set when ALC is active.
1
0(LSB) Slow Command in Execution. This bit is set during the execution of a Slow command.
Refer to Table 3-9.
7(MSB) Parity
6 Complement of bit 5
5 RF Inhibited . Bit is set if RF is inhibited.
4 Transmit Selected . Bit is set if Transmit is selected during Heater Time Delay.
3 Summary Fault . Bit is set if CHPA is latched into the Fault state.
2 CHPA Operating State
(see note 1)
1 CHPA Operating State
(see note 1)
2
0(LSB) CHPA Operating State
(see note 1)