Comtech EF Data SDM-650B - Manual (Page 284)

Asynchronous Overhead Channel Unit SDM-650B Satellite Modem
F–26 Rev. 5
BBLoopBk
(Test Mode Configuration
Option)
Programs the modem for baseband loopback operation.
When baseband loopback is turned ON, baseband terrestrial data is
looped back on the customer side of the interface.
Note: Asynchronous data is not looped back in the baseband loopback
operation.
On entry, the current status is displayed with the flashing cursor on the
first character. Use the arrow keys to select ON or OFF. Press [ENTER]
to execute the change.
INTF_LBk
(Test Mode Configuration
Option)
Programs the modem for interface loopback operation. When interface
loopback is turned ON, data is looped back on the modem side of the
interface.
On entry, the current status is displayed with the flashing cursor on the
first character. Use the arrow keys to select ON or OFF. Press [ENTER]
to execute the change.
Note: Interface loopback only works when the TX data rate matches the
RX data rate.
TX CODE Programs the transmitter for AMI, B8ZS, B6ZS, or HDB3 data.
On entry, the current coding format is displayed. Use the arrow keys to
select the desired coding format. Press [ENTER] to execute the
change.
RX CODE Programs the receiver for AMI, B8ZS, B6ZS, or HDB3 data.
On entry, the current coding format is displayed. Use the arrow keys to
select the desired coding format. Press [ENTER] to execute the
change.
TX 2047 Programs the TX 2047 pattern ON or OFF.
This test mode is only available when AUPC is turned ON in the Utility
menu.
On entry, the current status is displayed with the flashing cursor on the
first character. Use the arrow keys to select ON or OFF. Press [ENTER]
to execute the change.
BUF_SIZE This configuration function is used to set the size of the buffer.
On entry, the current buffer length is displayed. Use [
↑ ] and [ ↓ ] to select
the desired buffer size. The buffer size will be displayed in ms or bits.
Enter the Utility menu to change the buffer units to milli-seconds or bits.
32 to 262144 bits, in increments of 16, can be selected. If ms is
selected, 6 to 96 ms, in increments of 1 ms, can be selected. Press
[ENTER] to execute the change.
BUF_CNTR This configuration function is used to center the buffer.
Press [ENTER] twice to center the plesiochronous buffer.
TX BAUD Programs the transmitter baud rate.
On entry, the current transmitter baud rate is displayed with the flashing
cursor on the first character. Use [
↑ ] and [ ↓ ] to select the desired rate.
The baud rate may be programmed from 110 to 38,400 bit/s. Press
[ENTER] to execute the change.