Technical Manual

3. ELECTRICAL DESCRIPTION
16
LZT 123 7607 R1B
3.2 RS232 Serial and Extended I/O Interface
The GT47 supports a standard 9 signal RS232 serial interface (EIA/TIA
574) on the 15 pin high density connector together with a range of
configurabe I/Os including a second 4-wire 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 GT47 signal, via AT command or intrinsic
function, the corresponding GR47 signal name must be used, see GT47-
GR47 signal cross reference table
, page 21.
The electrical characteristics of the serial port signals are shown below:
1 DCD
2 RD
3 TD
4 IN-3
5 OUT-3
6 DSR
7 RTS
8 CTS
9 4.8V
1
2
3
6
7
8
13 14
10
10 RI
11 IN-2
12 OUT-4
13 DTR
14 GND
15 ANA_IN
4
5
9
11
12
15
Pin GT47
Signal
Dir Max.
Voltage
limits
Description
1 DCD O ±13.2V RS232 signal
Data carrier detect V
RXW
≥ ±5V
2 RD O ±13.2V RS232 signal:
Received data V
RXW
≥ ±5V
3 TD I ± 25V RS232 signal:
Transmitted data V
,/
< 0.6V, V
,+
> 2.4V
4 IN-3 I -0.5 - 32V Digital input V
,+
> 3V, V
,/
< 2.8V
PullDown with 40KΩ
5 OUT-3 O 32V, 0.25A low side switch, short circuit protected
6 DSR O ±13.2V RS232 signal:
Data set ready V
RXW
≥ ±5V
7 RTS I ±25V RS232 signal:
Request to send V
,/
< 0.6V, V
,+
> 2.4V
8 CTS O ±13.2V RS232 signal:
Clear to send V
RXW
≥ ±5V