RS4 High Channel Count Streaming

Tech Note: TN0989
Product: RS4, Synapse, RPvdsEx
Version: 90
Date Added: 2018-10-15


Improvements to the RS4 firmware have improved stability when streaming high channel count data to multiple ports on the RS4. This requires updates to the software (Synapse and RPvdsEx macros) and RS4 firmware.


Users streaming high channel count data to multiple RS4 ports require an additional setting. The "Use Larger Buffer Size" option allows more DSP memory to hold the data destined for the RS4, which improves reliability during the data transfer. The RS4 must be updated to v1.19 firmware to most effectively use this setting (more on that below).

In Synapse, this option is in the RS4 options:

If using OpenEx, this option is in the v90 Stream_Server_MC macro In RPvdsEx:

RS4 v1.19 Firmware Update:

It is recommended that all RS4 users update to the latest RS4 firmware. With the RS4 connected to the Internet, go to the Config tab and select "Update Firmware". The updates are incremental, so you may need to repeat this step several times until the version number at the top of the Ports tab says "v1.19".

In v1.19, the RS4 saves a log text file within each recording folder that tracks the starting and ending sample of each stream. It also makes audible beeps when a recording starts and stops, or if there is a transfer error during the recording.If there is a gap in the saved data stream (typically this would be caused by a physical problem with the fiber optic connection between the RZ2 and RS4), this will also be indicated in the log file, so the data can be aligned in post processing. If the gap is long enough, the RS4 will assume the recording has stopped and start new files when data comes in. This allowable gap is controlled by the "Rec Stop Timeout" setting on the Config tab Settings.