Microtronix Access User Guide
10.2.2.2 Tail Circuit Cables
If the port is configured to connect to another DCE using a tail circuit cable (
Clock source =
TxFromRx
), then a baud rate is chosen and the internal baud rate generator is used to source the
output RxC clock. Receive and transmit data use the ETxC (pin 24/11) to derive clocking.
Pin #
Direction Signal Name
17
output
RxC A
9
output
RxC B
24
input
TxC A
11
input
TxC B
The following table shows the pin configurations and connector types for each supported interface type.
DB25M
RS530
DB25M
RS232
DB25M
V.35
M/34M
RS449
DB37M
1
1
1
A
1
2
3
3
R
6
3
2
2
P
4
4
8
8
F
13
6
20
20
H
12
7
7
7
B
19, 37
8
4
4
C
7
9
11
W
35
10
19
25
11
9
X
26
14
16
T
24
16
14
S
22
17
24
24
U
17
19
10
31
20
6
6
E
11
22
23
30
23
22
29
24
17
17
V
8
10.2.3 Split clock configuration
When the primary WAN port is configured for split clock (
Clock source = TxInt
), the clock pins are
configured as shown in the table below. The receive clock (pin 17/9) is generated internally, and the
transmit clock is derived from the external source on pin 24/11. Pins 15/12 are not used and should be
left disconnected. Since this is a custom configuration, the cable may be either straight through or
crossover, depending on the application.
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