4-11TPS150 Switching and Transmission System • Serial Communications

Serial Commands

Communication protocols

The transmitter’s and receiver’s serial ports (figure 4-16) are factory-configured to
9600 baud, no parity, no flow control, half-duplex mode. If you change the
transmitter’s serial protocols, communications between the computer and the
transmitter are lost until the computer is updated to match the new transmitter
settings.
Connected
RS-232
device pin Function
TPS150
pin
1
2
3
4
5
6
7
8
9
—
RX
TX
—
Gnd
—
—
—
—
Not used
Receive data
Transmit data
Not used
Signal ground
Not used
Not used
Not used
Not used
51
96
Female
Figure 4-16 — Remote port pin assignments for the TPT150 and TPR150
The communications protocols of the receiver should match the protocols of the
device to be controlled.

Command and response structure

Valid commands consist of a leading delimiter, one or more characters in a
command code, and an ending delimiter. The transmitter’s response to an RS-232
command also consists of a leading delimiter, a command code, and an ending
delimiter.
The transmitter’s leading delimiter code is always a left bracket ( [ ). The ending
delimiter code is always a right bracket ( ] ).
Example: [CPp@] — where “[“ is the leading delimiter, “CPp@” is the command
(reset the transmitter’s serial port to default values), and “]” is the ending delimiter.

Addressing the transmitter

The transmitter must be addressed before it will accept and respond to commands.
The address packet ([CC##], where ## is the 2-digit address ) routes setup
information to a particular unit on a network and enables command responses.
Once the transmitter is addressed, it can accept an unlimited number of commands.
If a different unit is addressed, the TPT150 ignores subsequent commands until it is
addressed again.
The factory-installed default address is 97, but this number can be changed. The
transmitter can also take commands after receiving a broadcast address of 00, but it
does not send responses. Broadcast is for multiple units in a network configuration
in half duplex mode.
By definition, the display device connected to the receiver’s RS-232 port is assigned
an address that is one larger than the transmitter’s (for example, 98 to the
transmitter’s default 97). If you address the display, the transmitter passes the
commands received directly through to the receiver’s RS-232 port, allowing you to
control the display. The transmitter also passes responses on the receiver’s RS-232
port back to its own serial port.