Synchronous Modem Eliminator (SME-4M)
16
NOTE
The above chart shows all pins on the DB25 connector. The SME-4 only uses
Pins 1 through 8, 15, 17, 20, 21, 22, and 24.
FIgure 6-1. RS-232 Interface Female Connector
SIGNAL PIN
PIN
SIGNAL
DISTINATION
NUMBER
NUMBER
DESTINATION
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
PROTECTIVE GROUND
TRANSMITTED DATA
RECEIVED DATA
REQUEST TO SEND
CLEAR TO SEND
DATA SET READY
SIGNAL GROUND/COMMON RETURN
RECEIVED LINE SIGNAL DETECTOR
+ VOLTAGE
- VOLTAGE
SECONDARY RECEIVED LINE SIGNAL INDICATOR
SECONDARY CLEAR TO SEND
SECONDARY TRANSMITTED DATA
DCE TRANSMITTER SIGNAL ELEMENT TIMING
SECONDARY RECEIVED DATA
RECEIVER SIGNAL ELEMENT TIMING
SECONDARY REQUEST TO SEND
DATA TERMINAL READY
SIGNAL QUALITY DETECTOR
RING INDICATOR
DATA SIGNAL RATE SELECTOR
DTE TRANSMITTER SIGNAL ELEMENT TIMING
