How can I scan / detect the communication parameters of an existing data link? (Baud Rate scan, Data Bits, Stop Bits, Parity)

How can I scan / detect the communication parameters of an existing data link? (Baud Rate scan, Data Bits, Stop Bits, Parity)

Applies to: Docklight (all versions), Article ID: dl_faq048

Our advanced serial data monitoring hardware “Docklight Tap Pro” and “Docklight Tap 485” now supports a new Scan Mode. It performs automatic bit rate / baud rate detection for a running communication link and tries to determine the additional communication parameters Data Bits and “Parity.

To use the new feature, please download and install the extended Docklight software packages below. Then perform the following steps:

– If this is a Tap Pro purchased before 2018/01: Go to “Tools – Expert Options…”, “Hardware” section. Then click “Update Tap Pro” to make sure your Tap hardware uses a firmware version V2.6 (or higher).

– Go to “Tools – Project Settings…”, set up basic Monitoring Mode for your Tap, with Receive Channels usually “VTP0” and “VTP1”.

– In “COM Port Setting”, choose Baud Rate = “None”. (The last entry in the dropdown list.)

– Confirm and start monitoring (menu Run – Start Communication F5).

– The Tap Pro / Tap 485 now scans the communication independently in both directions. If serial data could be detected in either data direction, the settings are displayed as comments in the Docklight Communication Window. They are also are noted in the communications status bar under the main toolbar.

NOTE: The Tap Pro / Tap 485 continues to scan in regular intervals until you use Run -Stop Communication (F6). The communications parameters do not automatically become the new Project Settings. The results can be different for both directions and the accuracy depends also of the data pattern that could be seen on the serial line. So you have to make your own decision of what seems to be the correct Docklight Project Settings.

NOTE: Docklight tries to align the baud rate / bit timing results to a standard serial baud rates like 115200. But by design and due to usual tolerances of the baud rate generator in serial devices, there can be deviations and unusual/nonstandard values can appear. A +/- 3% tolerance window is usually within specs and not a mistake.

Docklight Scripting v2.2.x Customer Support – Baud rate scan / communication scan with Docklight Tap Pro and Docklight Tap 485

Docklight v2.2.x Customer Support – Baud rate scan / communication scan with Docklight Tap Pro and Docklight Tap 485