Cables and Connectors
Serial host interface specifications
MAX 4000 Series Hardware Installation Guide
Preliminary November 4, 1998
C-39
X.21 cabling
Ascend supplies a single X.21 cable. You can use the X.21 cable for connecting to generic
serial hosts. If your host is equipped with an X.21 interface, Figure C-21 and Table C-28 show
the pinouts for the host cable.
Figure C-21. X.21 cable to generic serial host
Table C-28. Pinouts for X.21 cable to generic serial host
Model Number MBHD-X21
Part number 2510-0098-001
Pair #
X.21 signal name
(MAX)
Equivalent V.35/RS-449
signal name
(MAX)
MAX male DB-44
(MAX)
Host female DA-15
1
G*
SGND*
25*
8
2
T(A)
T(B)
SD+
SD-
29
30
2
9
3
R(A)
R(B)
RD+
RD-
40
39
4
11
4
S(A)
S(B)
ST+
ST-
42
41
6
13
5
C(A)
I(A)
DTR
DCD
8
36
3
5