Digital Discovery UART at non-standard rates

[dbkincaid]

@attila I saw your reply to another user that requested UART log directly to file.  I have the same request for my Digital Discovery, but I am not running at a standard rate (UART 4MHz) so I cannot use the protocol analyzer.  I am able to do normal "logic" capture and set up UART on the line at the 4M rate.   This decodes properly but I cannot capture all the transaction series with one capture.

I would like to be able to capture the decoded UART bytes directly to file until I stop the capture.  (I am not interested in the digital lines)

I would also like to be able to set up two UART lines (basically a sniffer to watch TX and RX traffic).  They are running at the same 4M rate.

Let me know if you would like more information.

-Brian

 

[attila]

Hi @dbkincaid

You can use the Protocol tool to spy on one UART line with (Send&Received tab). You can enter any desirable rate. In this mode only the decoded bits are stored. In case the average UART transfer is less than ~1Mbps it will work.

In the UART Spy tab in order to capture multiple UART lines the decoding is done in software. Lot of data is streamed to the PC limiting the UART rate to ~200kbps.
To capture multiple lines at high frequency the Logic Analyzer should be used repeated or record mode.