
26
NON-POWERED INTERFACE CONVERTERS
Fig. 3-9. RS-449 (V.36) DTE/RS-232 (V.24) DCE
Schematic Diagram.
Shield
1
Frame GND
1
Signal GND
19,37,20
Signal GND
7
7
RTS
4
CTS
DSR
DTR
DCD
9
5
11
6
12
20
13
8
25
R
27
R
29
R
30
R
31
R
5
23
TC
15
17
26
RC
17
17
35
EXT-TC
24
4
22
TC
2
6
24
RD
3
+
-
+
-
10
LL
NC
14
RL
NC
18
TM
NC
18
LL
21
RL
25
TM
V.36 (DTE)
V.24 (DCE)
R = 100
Ω
ST-a
ST-b
RT-a
RT-b
TT-a
TT-b
SD a
SD-b
RD-a
RD-b
RS-a
CS-a
DM-a
TR-a
RR-a
RS-b
CS-b
DM-b
TR-b
RR-b