 | Article ID: 1600 |
| Q&A | |
DSU III AR Interface Pinouts
Q:
DSU III AR Interface Pinouts
A:
The following charts give the pin assignments for the III AR interfaces. They can also be found in the DSU III AR User Manual.
Pin Assignments for Telco Connector
The DSU III AR has an eight-position modular jack labeled TELCO. The connector is used for connecting to the network when the unit is configured for either dedicated or switched operation.
| Pin | Name | Description |
|---|---|---|
| 1 | R1 | Transmit Data from DSU to Network-Ring 1 |
| 2 | T1 | Transmit Data from DSU to Network-Tip 1 |
| 3-6 | - | Not Used |
| 7 | T | Receive Data from Network to DSU-Tip |
| 8 | R | Receive Data from Network to DSU-Ring |
DTE DATA CONNECTION/PRIMARY DTE
The primary DTE should be connected to either the EIA-232 DTE connector or the CCITT V.35 DTE connector. The maximum cable lengths recommended are 50 feet for the EIA-232, and 100 feet for the CCITT V.35.
The V.35 connector is recommended for use with data rates above 19.2 kbps. The EIA-232 connector works up to 56 kbps with a low capacitance cable or with the external transmit clock option selected. The primary DTE rate is configured from the front panel. The primary DTE can operate in asynchronous or synchronous modes.
To prevent possible radio frequency interference emissions, a shielded cable is required.
Pin Assignments for Primary EIA-232 Connector
| Pin | EIA | Description |
|---|---|---|
| 1 | AA | Protective Ground (PG) |
| 2 | BA | Transmit Data (TD) |
| 3 | BB | Receive Data (RD) |
| 4 | CA | Request to Send (RS) |
| 5 | CB | Clear to Send (CS) |
| 6 | CC | Data Set Ready (SR) |
| 7 | AB | Signal Ground (SG) |
| 8 | CF | Received Line Signal Detector (CD) |
| 9 | - | +12 Test Point |
| 10 | - | -12 Test Point |
| 15 | DB | Transmit Clock (TC) |
| 17 | DD | Receive Clock (SCR) |
| 18 | - | Local Loopback (LL) |
| 20 | CD | Data Terminal Ready (TR) |
| 21 | - | Remote Loopback (RL) |
| 22 | CE | Ring Indicator (RI) |
| 24 | DA | External Tx Clock (ETC) |
| 25 | - | Test Indicator (TI) |
Pin Assignments for Primary V.35 Connector
| Pin | EIA | Description |
|---|---|---|
| A | 101 | Protective Ground (PG) |
| B | 102 | Signal Ground (SG) |
| C | 105 | Request to Send (RS) |
| D | 106 | Clear to Send (CS) |
| E | 107 | Data Set Ready (SR) |
| F | 109 | Received Line Signal Detector (CD) |
| H | - | Data Terminal Ready (TR) |
| J | - | Ring Indicate (RI) |
| L | - | Local Loopback (LL) |
| N | - | Remote Loopback (RL) |
| R | 104 | Receive Data (RD-A) |
| T | 104 | Receive Data (RD-B) |
| V | 115 | Receiver Signal Element Timing (SCR-A) |
| X | 115 | Receiver Signal Element Timing (SCR-B) |
| P | 103 | Transmitted Data (SD-A) |
| S | 103 | Transmitted Data (SD-B) |
| Y | 114 | Transmitter Signal Element Timing (SCT-A) |
| AA | 114 | Transmitter Signal Element Timing (SCT-B) |
| U | 113 | External TX Signal Element (SCX-A) |
| W | 113 | External TX Signal Element (SCX-B) |
| NN | - | Test Indicator (TI) |
SECONDARY CHANNEL CONNECTION
If used, the secondary DTE should be connected to the auxiliary EIA-232 connector.
Pin Assignments for Auxiliary EIA-232 Connector
| Pin | EIA | Description |
|---|---|---|
| 1 | AA | Protective Ground (PG) |
| 2 | BA | Transmit Data (TD) |
| 3 | BB | Receive Data (RD) |
| 4 | CA | Request to Send (RS) |
| 5 | CB | Clear to Send (CS) |
| 6 | CC | Data Set Ready (SR) |
| 7 | AB | Signal Ground (SG) |
| 8 | CF | Received Line Signal Detector (CD) |
