Test Serial Communications Links
tProbe™ Datacom Analysis and Emulation
13th, Jul 2018
Welcome to another July 2018 issue of GL Communications' newsletter providing information on our latest tProbe™ Datacom Analyzer/Emulator, a tool that is designed for test and verification of data communications circuits and equipment.
GL's Datacom Analyzer/Emulator is an optional board available with GL's tProbe™ T1 E1 Analyzer or as a standalone unit. It is designed for test and verification of data communications equipment and circuits - specifically serial interfaces that provide clock, data, and control signals. These are commonly encountered in military links, satellite circuits, WAN, and data modem interfaces.
Supported Line interface standards include - V.35, V.24, X.21, RS-232C, RS-449, RS-485, EIA-530 and EIA-530A Various cables are provided for these interfaces to make testing convenient.
Example: The mainframe data being corrupted or in error is a common problem that might occur.
To test this interface, we would need to connect a V.35 interface on the DSU to the mainframe connection and transmit data through the DSU to the corresponding point on the other side of the network. This helps us to verify that the DSU and network are operating correctly, or the main frame has a problem with the V.35 interface. In this case, we would use tProbe™ Datacom as a CSU/DSU and run BERT at 6 Mbps rate end to end to verify the connection and interfaces. An example of the commonly used DSU would be ADTRAN T3SU 300 or equivalent equipment.
- DTE and DCE emulation for end-to-end testing of data networks; Software selectable modes are provided to emulate DTE, DCE.
Verifying end-to-end transmission through DCE or DTE bidirectional non-intrusive monitoring for a greater level of troubleshooting for data networks.
- Perform Frequency Measurement, PPP Analysis, and HDLC Analysis tests as per user-defined frequency (data rate) definitions for various encoding options listed below
- Synchronous (sync) BER from 300 b/s to 16.384Mbps
- Asynchronous (async) BER from 300 b/s to 115.2Kbps
- NRZ, and Differential Manchester encoding schemes
- Manchester FM0 and FM1 BER from 75 b/s to 1.024Mbps
- Manchester IEEE 802.3 BER from 75 b/s to 115.2Kbps
- Manchester GE Thomas BER from 75 b/s to 115.2Kbps
- Differential Manchester BER from 75 b/s to 115.2Kbps
- Manchester FM0 and FM1 BER from 75 b/s to 115.2Kbps
- NRZI BER from 0.5Mbps to 10Mbps
- Supports Handshaking signals control and monitoring
- Full control and monitoring of RXD, RXC, TXC, CTS, DSR, DCD, DTR, RI, TM signals
- Simulate Impairments on DTE-DCE Link using HDLC Link impairment utility
- HDLC Tx/Rx and Impairment
This application helps us understand the delay a network can handle, simulate inline error insertions, transmit / receive HDLC frames, control error rate to correct the network. It also provides numerous error counters such as total number of CRC, Logic, Drop Frame, Change, and Duplicate errors.
- Protocol Analysis
Datacom analyzer supports capture, decode, and analysis of HDLC, Frame Relay, and PPP protocols. One can use HDLC Tx/Rx application along with HDLC analysis to test end-to-end serial link performance as shown in the image below. The tProbe™ Datacom also supports Frame Relay and PPP protocols analysis on a similar note. The Significant features have been added to all protocol analysis applications to enhance troubleshooting features, as listed below -
- Extensive filter and search capabilities
- Any protocol field can be added to the summary view, filtering, and search features providing users more flexibility to monitor required protocol fields.
- Support multithreaded offline filters
- Joining multiple periodically saved offline files to analyze at once. This also supports predefined filters applied to offline filter while saving.
- Improved filtering performance in protocol analyzer
- Monitoring of Control Signals and Frequency
Displays the signal activity on the Datacom DCE and DTE interfaces along with the frequency measurements for each port.
This application permits viewing unframed data on a Datacom port. Approximately 2 seconds of data is captured for viewing.
- Record/Playback Applications
This application permits record/playback to/from file across DTE/DCE interfaces. The three application provided are: Playback from File, Automated Record Playback , Automated Continuous Capture.
- Error Insertion
The Error Insertion application permits inserting single, fixed, automatic, random, and burst error into the incoming or outgoing bit stream.
- Precision Delay Measurement
Precision Delay Measurement measures the Round Trip Delay of a system. Sending a BER pattern with the insertion of an error bit and timing the reception of the error bit do the Round Trip Delay measurement. Measurement is precise and accurate to the microsecond level.
- Rx to Tx Loopback
This application is used in conjunction with a Bit Error Rate Test to verify the operation of the datacom analyzer.
- Bit Error Rate Test
The Bit Error Rate Test (BERT) application generates/detects Pseudo Random Bit Sequences (PRBS) for testing performance of data communication circuits.