Service manual

EXTERNAL SERIAL CONTROL PROTOCOL
B-26
April 2001
Part No. 001-9800-203
B.6.2 COMMAND MESSAGES
CMD ENTER REMOTE MODE
Function
: Requests that the subscriber unit switch to
the remote command mode. No other external
devices should be connected or registered when
this message is sent. If any are or if the external bus
is in multi-drop mode, a NAK message response is
sent.
If the subscriber unit is personality programmed for
“remote mode only” operation, this message is sent
as a broadcast (unacknowledged) message when
subscriber unit start-up is completed. The remote
device does not have to register and should just
assume device address 0x02.
Format:
Data: None
CMD EXIT REMOTE MODE
Function
: Requests that the subscriber unit switch to
the standard command mode. The subscriber unit
will attempt to resume normal operation. This
command causes a “warm” restart of the subscriber
unit. On restart, no external devices are considered
to be registered. If this command is sent and the
subscriber unit has been programmed for “remote
command mode” only operation, a power on reset
is performed and remote command mode is
restarted.
Format
:
Data
: None
CMD REMOTE NOTIFICATIONS
Function
: Requests that the subscriber unit switch to
the remote command mode. All other external
devices are commanded to perform a directed
power down disconnect before this message is
acknowledged. If the subscriber unit is personality
programmed for “remote mode only” operation,
this message is sent as a broadcast (unacknowl-
edged) message when subscriber unit start-up is
complete.
Format
:
Data
:
Flags:
Bit flags indicating the external device wants
the notification type (bit = 1) or does not want
the notification type (bit = 0). On Subscriber
Unit reset, all notifications are disabled (see
Table B-6).
Conv Rate: Analog to Digital conversion rate. Set
the time between INFO A TO D messages in
~250 millisecond intervals. If set to zero, INFO
A TO D messages are not sent.
CMD SET CALL GUARD
Function
: Commands the subscriber unit to set the
requested Call Guard code. Call Guard values are
octal encoded. Digital Call Guard settings are
already encoded this way. For tone Call Guard
squelch, the Call Guard table entry number (see
Call Guard table at end of Section 4), must be
converted into an octal number.
Format
:
Opcode
1 byte
0x21
Opcode
1 byte
0x22
Opcode Flags Conv Rate
1 byte 1 byte 1 byte
0x23
Opcode
Tx Call Guard
Code
Rx Call Guard
Code
1 byte 1 byte 1 byte
0x24