HP 8920A, User Manual

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Chapter 10, Signaling Encoder (AF Generator 2)
MPT 1327 Encoder
Traffic Channel
The
Traffic Channel
field allows you to enter the traffic channel number. The
traffic channel is a four-digit decimal integer without leading zeros. It has the
range 0 through 1023, and its default value is 1.
Undisplayed Controls
Some MPT 1327 controls are not displayed on the encoder screen; they are only
accessed using IBASIC commands over HP-IB. These controls include the delay
parameter, the SYNC and SYNT synchronization codewords, and the message
and filler buffers.
The controls listed in the remainder of this section are not displayed on the MPT
1327 Encoder screen.
Delay Parameter for Repeat Transmissions
This control is only available using IBASIC commands; it is not displayed on the
MPT 1327 Encoder screen.
In the aloha message there is a bit field which indicates to the radio unit (RU) how
long it should wait for a response from the TSC. If the RU does not receive a
response within this period it should re-issue the request. This is generally set to a
fixed value determined by the protocol speed and the responsiveness of IBASIC.
In some circumstances it may be useful to change this value.
The delay parameter has a range 0 through 7, with a default value of 7.
This control is listed as
RDELay
in the HP-IB Syntax Diagrams in the
Programmer’s Guide.
Table 10 Delay Parameter to Actual Response Delay
Delay Parameter Response delay
0 0
1 1
2 2
3 3
4 4
5 5
6 10
7 15