AMX Precis LT User Manual

Attaching an External Controller
The Precis
LT
Distribution Matrix can be controlled by attaching an external controller
(computer, AMX, Crestron, etc.) to the Precis
LT
using the RS-232 serial port
(DB-9 connector). An external controller is any device that can send and receive
ASCII code via RS-232. The steps below are specifically for establishing external
control using a personal computer (PC) and HyperTerminal software; however, other
external devices and terminal emulation programs can be used.
The Precis
LT
does not allow for hardware flow control. The pinout for the null
modem cable is illustrated in Figure 16.
To establish serial communication:
1. Plug one end of the null modem cable into the RS-232 (DB-9) serial port on the
Precis
LT
(see Figure 17).
2. Plug the other end of the null modem cable into the serial port on the PC.
14 Installing the Precis
LT
Attaching an External Controller
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
6
7
8
9
35124
Figure 16: RS-232 pin diagram (no hardware flow control)
PC: DB-9
AutoPatch: DB-9
PC: RS-232
AutoPatch: RS-232
#5GND.....................#5GND
#2RXD.....................#3TXD
#3TXD......................#2RXD
Figure 17: Connect the null modem cable to the serial port
Serial Port
Cable to External Control Device

AMX Precis LT Specifications

General

Brand	AMX
Model	Precis LT
Category	Matrix Switcher
Language	English