User's Manual

Table Of Contents
GC864 Hardware User Guide
1vv0300874 Rev.0 – 2010-01-25
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved. Page 36 of 64
Operating Range Interface levels (2.8V CMOS)
Level Min Max
Input high level V
IH
2.1V 3.1V
Input low level V
IL
0V 0.5V
Output high level V
OH
2.2V 3.0V
Output low level V
OL
0V 0.35V
The table below shows the signals of the GC864-QUAD V2 / GC864-DUAL V2 serial
port:
RS232 Pin
Number
Signal GC864-
QUAD V2 /
GC864-
DUAL V2
Pad
Number
Name Usage
1
DCD –
dcd_uart
32 Data Carrier Detect
Output from the GC864-QUAD V2 / GC864-DUAL V2
that indicates the carrier presence
2
RXD –
tx_uart
26 Transmit line *see Note
Output transmit line of GC864-QUAD V2 / GC864-
DUAL V2 UART
3
TXD –
rx_uart
25 Receive line *see Note
Input receive of the GC864-QUAD V2 / GC864-DUAL
V2 UART
4
DTR –
dtr_uart
29 Data Terminal Ready
Input to the GC864-QUAD V2 / GC864-DUAL V2 that
controls the DTE READY condition
5 GND 5,6,7 Ground ground
6
DSR –
dsr_uart
27 Data Set Ready
Output from the GC864-QUAD V2 / GC864-DUAL V2
that indicates the module is ready
7
RTS –
rts_uart
31 Request to Send
Input to the GC864-QUAD V2 / GC864-DUAL V2 that
controls the Hardware flow control
8
CTS –
cts_uart
28 Clear to Send
Output from the GC864-QUAD V2 / GC864-DUAL V2
that controls the Hardware flow control
9 RI – ri_uart 30 Ring Indicator
Output from the GC864-QUAD V2 / GC864-DUAL V2
that indicates the incoming call condition
*NOTE:
According to V.24, RX/TX signal names are referred to the application side, therefore
on the GC864-QUAD V2 / GC864-DUAL V2 side these signal are on the opposite
direction: TXD on the application side will be connected to the receive line (here
named TXD/ rx_uart ) of the GC864-QUAD V2 / GC864-DUAL V2 serial port and vice
versa for RX.