User's Manual

3-6
Table 3-1. Remote Responses
CODE NAME DESCRIPTION
ACK Acknowledge Response from the transceiver to a valid RCU command. If the
command requires data from the transceiver, the data is sent first,
followed by ACK.
NAK No Acknowledge Response from the transceiver to an invalid RCU command.
HT New
acknowledge
A response from the transceiver indicating that the transceiver was in
the keypad (manual) command mode at the time it received a remote
command. The transceiver changes mode to the remote command
mode and sends HT. This acknowledge is used instead of an ACK for
the first valid remote command received when transceiver was in
keypad command mode.
The RCU cannot send a new command until it receives an ACK/NAK/HT or times out,
whichever occurs first. If the RCU receives a NAK or times out, send the Z command to re-
establish sync with the transceiver.
Provisions must be made on the RCU side to poll the status of the transceiver especially in
the over-temp, scan, and synth lock conditions. Another provision that the RCU should make is
that after three (3) NAKs from the transceiver for the same command, the RCU should display an
error code to indicate that an interface problem or an invalid command has occurred.
The RCU (handset or control head) should display the status on its LCD display only after it
has queried the transceiver for data. In this way, the RTU and the transceiver displays will always
agree.
NOTE
To conserve power, the RS232 transmitter in the transceiver is
automatically turned off after an ACK or HT is sent. This
essentially puts the TX in the break state. The remote software
must handle any special interrupts etc. that may occur as a result
of a break.
3-3.2. REMOTE CONTROL CODES
The following tables show the remote control command codes for the URC-200 (V2)
Transceiver. The commands are organized as follows:
 Remote Transceiver Operation Commands
 Transceiver Customizing Commands

Transceiver Status Inquiry Commands
The codes for the basic transceiver as well as those for the available options are included in
the tables. The available options are:
 30 - 90 MHz extended frequency option, EBN-30
 400 - 420 MHz extended frequency option, EBN-400
 8.33 kHz tuning increment / channel spacing option, ECS-8
Many of the commands are only valid for certain transceiver configurations and frequency
ranges, Table 3-2 provides a mapping of these dependencies. In Table 3-3, the commands
affected by these dependencies are indicated by a reference to “Note 1” below the command. For
example, if the transceiver is equipped with the 30-90 MHz option, AM is not available, but FM,
PT and CT are, including the other parameters in the remainder of the column. Similarly, 8.33
kHz tuning is available only for the 115 - 173.995 MHz and 225 - 399.995 MHz bands.