Lear Siegler ADM 3A - Page 22

____ LEAR SIEGLER, INC.
DATA PRODUCTS DIVISION
ADM 3A
EXTENSION
MODEM
J1
J2
1
1
ETXD
2
BREAK KEY
TRANSMIT DATA
2
TXD
TRANSMIT
SERIAL
DATA
GATED PORT
ERXD
3
RECEIVE
DATA
3 RXD
103·202
LOCAL
4 RTS
ERTS 4
ECTS
5
CLEAR TO SEND
5
CTS
EDSR
6
Ct.-iA SET READY (NOT USED IN DISPLAY)
6 DSR
7
-¥
7
-
.
EOCD
a
8
DCD
EDTR 20 t----t
EDTR
UDTR
>---....., 20 DTR
ECLRXD· 17
20MA CURRENT 2~A CURRENT
17
Cl TXD-
8 I
01 RECTIONAl
ECLRXD·
24
LOOP RECEIVER
LOOP TRANSM ITTE R
24 CLTXD-
ECLTXD+
23
23
CLRXD~
20MA CURRENT
81 DIRECTIONAL
20MA CURRENT
ECl TXD·
25
LOOP RECEIVER LOOP RECE IVER
Z5
CLRXD·
Figure 2·4. Modem and RS·232C Extension Interface Logic
2-6