Comtech EF Data C5 - Manual (Page 145)

C5/K1/K3 Integrated Satellite Terminal System Operation
Rev. 0 4–19
BUFFER CLOCK Programs the interface buffer output clock to one of the following
modes:
! RX (SATELLITE): Sets the output buffer clock to the
satellite clock.
! SCT (INTERNAL): Sets the buffer clock to operate from
the modem internal clock. This is also the fallback clock.
! EXT. CLOCK: Sets this clock source to the external clock.
! TX TERRESTRIAL: Sets the buffer output clock to
recover timing from the incoming TX data clock.
! INSERT CLOCK: Selects the recovered clock from the
insert send data input received from the terrestrial
equipment.
Upon entry, the current setting of the plesiochronous buffer clock is
displayed. Press [
$] or [%] to make the selection. Press [ENTER] to
execute the change.
RX CLOCK PHASE Programs the RX clock phase to Normal or Inverted.
Upon entry, the status of the RX Clock is displayed. Press [
$] or [%]
to make the selection. Press [ENTER] to execute the change.
B-BAND LOOP BACK
(Test Mode Configuration)
Programs the modem for baseband loopback operation.
When baseband loopback is turned on, the data and timing signals are
switched from the demodulator to the modulator on the modem side
of the interface. The DTE baseband signals are also looped back from
the transmitter data and clock to receiver data and clock on the
customer side of the interface. This is a bi-directional loopback of the
baseband data. Refer to Figure 4-22 for a block diagram of baseband
loopback operation.
Upon entry, the status is displayed. Press [
$] or [%] to make the
selection. Press [ENTER] to execute the change.
BUFFER SIZE Sets the size of the buffer.
Upon entry, the current buffer length is displayed. Press [
$] or [%] to
select the desired buffer size. The buffer size is displayed in seconds
or bits. Enter the Utility Interface menu to change the buffer units to
seconds or bits. If selecting seconds, choose from 1 to 99 ms, in
increments of 1 ms or 0 (Bypass). If selecting bits, choose from
32 to 262144 bits, in increments of 16 bits. Press [ENTER] to execute
the change.
Note: To have the modem calculate the plesiochronous shift, set the
buffer units to ms. When a specific buffer depth is desired, set the
buffer units to bits. Select bits or ms from the Utility Interface
menu.
BUFFER CENTER This configuration function is used to center the buffer. Choosing
YES centers the buffer.
Press [ENTER] twice to center the buffer.