User Manual

5. ELECTRICAL DESCRIPTION
25
LZ T 123 7605 P1C
5.2 RS232 Serial and Extended I/O Interface
The Control Terminal supports a standard 9 signal RS232 serial interface
(EIA/TIA 574) on the 15 pin high density connector together with a range
of configurable I/Os including a second 4-wire logic level RS232 interface.
Signals that support an alternative configuration can be reconfigured using
the appropriate AT command (e.g. AT+E2IO) or via an intrinsic function
if using an embedded application.
Note! When reconfiguring a Control Terminal signal, via AT command or
intrinsic function, the corresponding Radio Device signal name must be
used, see Control Terminal-Radio Device signal cross reference table,
page 30.
The electrical characteristics of the serial port signals are shown below:
12 OUT-4
7 RTS
2 RD
13 DTR
8 CTS
3 TD
1
2
3
6
7
8
13 14
10
4
5
9
11
12
15
11 IN-2
6 DSR
1 DCD
15 ANA_IN
10 RI
5 OUT-3
14 GND
9 4.8V
4 IN-3
Pin Control
Terminal
Signal
Dir Max.
Voltage
limits
Description
1 DCD O ±13.2V RS232 signal
Data carrier detect V
out
±5V
2 RD O ±13.2V RS232 signal:
Received data V
out
±5V
3 TD I ± 25V RS232 signal:
Transmitted data V
IL
< 0.6V, V
IH
> 2.4V
4 IN-3 I -0.5 to 32V Digital input V
IH
> 3V, V
IL
< 2.8V
PullDown with 40k
5 OUT-3 O 32V, 0.25A low side switch, short circuit protected
6 DSR O ±13.2V RS232 signal:
Data set ready V
out
±5V
7 RTS I ±25V RS232 signal:
Request to send V
IL
< 0.6V, V
IH
> 2.4V