X.21
X.21 defines differential signals on a DB-15 connector. Configure a port for RS-422/485/530 and use the
MicroGate X.21 cable (Part # 2515FM).
The mapping of the X.21 signals to the card signals are shown below.
Maximum data rate is 10Mbps. Cable length and signal loading may reduce the maximum data rate.
X.21 Male DTE
Signal
Electrical
HD-26 Pin
DB-25 Pin
DB-15 Pin
Direction
T(-/A), Transmit Data
RS-422/V.11
8
2
2
Output
R(-/A), Receive Data
RS-422/V.11
17
3
4
Input
I(-/A), Indicator (DSR/DCD)
RS-422/V.11
19,22
6,8
5
Input
Signal Ground
14
7
8
S(+/B), Clock Input (TxC, RxC)
RS-422/V.11
11,26
9,12
13
Input
I(+/B), Indicator (DSR/DCD)
RS-422/V.11
21,20
10,22
12
Input
X(+/B), Clock Output (AuxClk)
RS-422/V.11
7
11
14
Output
T(+/B), Transmit Data
RS-422/V.11
9
14
9
Output
S(-/A), Clock Input (TxC, RxC)
RS-422/V.11
25,10
15,17
6
Input
R(+/B), Receive Data
RS-422/V.11
18
16
11
Input
C(-/A), Control (DTR)
RS-422/V.11
3
20
3
Output
C(+/B), Control (DTR)
RS-422/V.11
4
23
10
Output
X(-/A), Clock Output (AuxClk)
RS-422/V.11
6
24
7
Output
X.21 Cable (Part# 2515FM )
