Lutron Electronics RadioTouch RTA-RS232 Setup And Installation Manual page 18

Notes on Protocol
Reply Back
The RTA-RS232 has the ability to reply to the host whether it processed the last command successfully or not.
This mode can be turned on or off. If Reply Back is turned on, and the RTA-RS232 successfully processes a
command, the RTA-RS232 will respond to the host with:
~OK<CR>
In addition, if the RTA-RS232 is in Configuration Mode and Reply Back Mode is on, the RTA-RS232 will echo
back the last command upon successful completion. For instance, if Zone 1 is to be configured as lights; the
following data is transferred
Host
RTA-RS232
If the command is not successfully processed by the RTA-RS232, it will respond to the host with:
~ERROR, error number <CR>
See Error Codes on page 26 for a list of error numbers and error descriptions. The default setting for Reply Back
Mode is ON.
Acknowledge
The RTA-RS232 has the ability to inform the host when it has completed RF transmission of an RS232 command.
This mode can be turned on or off. After completing RF transmission, the RTA-RS232 will respond to the host
with:
~ACK<CR>
The default setting for Acknowledge Mode is OFF.
ADD/DELETE RTA-RS232
Each utilized zone of the RTA-RS232 needs to be addressed to the RF Controller(s) it is intended to control. See
the RadioTouch Installer's Guide, part number 031-200, for information on addressing.
TM
Data Flow Control
The RTA-RS232 Interface can only accept one command at a time. When it is done processing this command, it
will inform the host it is ready to receive more data. The method by which it informs the host depends whether it is
using Hardware Handshaking, Software Flow Control or No Flow Control.
Hardware Handshaking
The RadioTouch RS232 interface supports full hardware handshaking. In this mode, the system utilizes TX, RX,
TM
CTS, RTS, DTR, DSR, and Ground.
Software Flow Control
If hardware handshaking is not being used, care must be taken to ensure all messages are captured. Once the
Host issues a command, it cannot issue another one until the RTA-RS232 issues a prompt "!" (ASCII 33d).
No Flow Control
In No Flow Control Mode the RTA-RS232 will not provide any indication that it is able to receive more data from
the host. In order to prevent messages from being lost, the host must ensure that each message transmitted to
the RTA-RS232 is separated by at least 400ms. No Flow Control is the default setting.
18 RadioTouch Setup Guide for RTA-RS232
TM
:CON,TYPE,1,L<CR>
~CON,RPT,TYPE,1,L<CR>