Specifications

55
Schneider Electric
Interfaces (continued)
The right cable
The serial link cable between the modem and the PC/Mac/terminal (DTE) should
include all the necessary signals.
b DB-25 and DB-25:
Note: General example used in most applications.
b DB-9 and DB-25:
Note: The DB-9 connector is often used on PCs.
b Mini-DIN and DB-25:
Note: The Mini-DIN 8 connector is used on Macintosh computers (DTE).
Most cables linking the modem to the
telephone jack comply with the international
connection standard. This standard is not
the same as the standard used in
Switzerland.
E52344
ab
ab
1
2
3
Telecommu
-
nications
line
T+T 83
PSTN
LINE
a
b
PHONE
American modem
ab
ab
1
2
3
Telecommu
nications
line
T+T 83
Swiss telephone
DTE (DB-25) MODEM (DB-25)
1 Protective Ground 1
2 Transmitted Data (TD) 2
3 Received Data (RD) 3
4 Request to Send (RTS) 4
5 Clear to Send (CTS) 5
6 Data Set Ready (DSR) 6
7 Signal Ground 7
8 Data Carrier Detect (DCD) 8
9 Data Terminal Ready (DTR) 20
22 Ring Indicator (RI) 22
DTE (DB-9) MODEM (DB-25)
1 Data Carrier Detect (DCD) 8
2 Received Data (RD) 3
3 Transmitted Data (TD) 2
4 Data Terminal Ready (DTR) 20
5 Signal Ground 7
6 Data Set Ready (DSR) 6
7 Request to Send (RTS) 4
8 Clear to Send (CTS) 5
9 Ring Indicator (RI) 22
DTE (Mini-DIN8) MODEM (DB-25)
1 DTR (RTS & DTR) 4 & 20
2 DSR (CTS) 5
3 TD Transmitted Data (TD) 2
4 & 8 (Ground) 7
5 RD Received Data 3
7 DCD (DCD) 8
SHIELD 1
Guide to Integration
Modbus / Jbus