V.35 Cable Assemblies
V.35 Interface Cables are used on DTE or DCE equipment
interfacing to a high-speed digital carrier. They meet the
CCITT Standard for Data Transmission. The Assemblies are Low
Capacitance shielded cable with 34 pin Connectors.
General Information
V.35 is a partially balanced, partially single-ended
interface specification. The data leads and clock leads
are balanced, the handshake leads are single-ended. Most
commonly used for 56kbps and 64kbps data rates.
| |
DATA LEADS
|
CONTROL LEADS
|
| Vdc
|
B > A
|
A > B
|
-3 to -25
|
+3 to +25
|
| binary
|
1
|
0
|
1
|
0
|
| signal
|
MARK
|
SPACE
|
MARK
|
SPACE
|
| function
|
off
|
on
|
off
|
on |
Transmitter output voltage from a balanced tranmitter
indicating a MARK is +0.35Vdc for the B line, -0.2Vdc for
the A line. Indication of a SPACE condition is +0.35Vdc for
the A line, -0.2Vdc for the B line. Output voltage
difference is 0.55Vdc. To make sense to the receiver it must
be at least 0.01Vdc difference between the A line and B
line. Maximum cable length depends on required speed and
cable capacitance. The extremes specified are 2000ft/600m to
4000ft/1200m @ 100kbps, 300ft/90m at 10Mbps. Sync
applications only, no async V.35 equipment around.
More speed/distance equations: 610m @ 64 kbps.
Pinning
 |
 |
| M/34 Male |
M/34 Female |
| Pin |
Signal |
Abbr. |
DTE |
DCE |
| A |
Chassis Ground |
|
- |
- |
| B |
Signal Ground |
|
- |
- |
| C |
Request To Send |
RTS |
Out |
In |
| D |
Clear To Send |
CTS |
In |
Out |
| E |
Data Set Ready |
DSR |
In |
Out |
| F |
Data Carrier Detect |
DCD |
In |
Out |
| H |
Data Terminal Ready |
DTR |
Out |
In |
| J |
Local Loopback |
LL |
In |
Out |
| K |
Local Test |
|
Out |
In |
| L |
Unassigned |
| M |
Unassigned |
| N |
Unassigned |
| P |
Send Data A |
TxD- |
Out |
In |
| R |
Receive Data A |
RxD- |
In |
Out |
| S |
Send Data B |
TxD+ |
Out |
In |
| T |
Receive Data B |
RxD+ |
In |
Out |
| U |
Terminal Timing A |
|
Out |
In |
| V |
Receive Timing A |
|
In |
Out |
| W |
Terminal Timing B |
|
Out |
In |
| X |
Receive Timing B |
|
In |
Out |
| Y |
Send Timing A |
|
In |
Out |
| Z |
Unassigned |
| AA |
Send Timing B |
|
In |
Out |
| BB |
Unassigned |
| CC |
Unassigned |
| DD |
Unassigned |
| EE |
Unassigned |
| FF |
Unassigned |
| HH |
Unassigned |
| JJ |
Unassigned |
| KK |
Unassigned |
| LL |
Unassigned |
| MM |
Unassigned |
| NN |
Unassigned |
There are two versions of V.35 screw locks. The
US-version measures 16/10 mm (the large one), the French
version measures 10/10 mm (the small one). The US-version is
also known as Domestic and the French version is also called
International.
V.35 Cross Cable
| A |
- |
A |
| B |
- |
B |
| C |
- |
F |
| F |
- |
C |
| E |
- |
H |
| H |
- |
E |
| R |
- |
P |
| T |
- |
S |
| P |
- |
R |
| S |
- |
T |
| V |
- |
U |
| X |
- |
W |
| U |
- |
V |
| W |
- |
X |
|
