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Reply To: Linking two Mayfly Boards Together

Home Forums Mayfly Data Logger Linking two Mayfly Boards Together Reply To: Linking two Mayfly Boards Together


    Hi @shicks (and thanks @neilh20),

    Thanks for that.  I am using a Yosemitech Y511-A with a Hydros CTD (Gen 1).  My code is fairly similar to yours.  I notice that you use pin 22 to power the Y511 (line 145) where I have ‘-1’.  I also don’t see the line ‘<span class=”crayon-i”>AltSoftSerial</span> <span class=”crayon-v”>altSoftSerial</span><span class=”crayon-sy”>(</span><span class=”crayon-cn”>6</span><span class=”crayon-sy”>,</span><span class=”crayon-cn”>5</span><span class=”crayon-sy”>)</span><span class=”crayon-sy”>;'</span> in my code.  Do you think this could be causing the problem?

    FYI, more information (and my current code) can be found in this post:


    Since posting the topic above I have attached ferrite collars to no avail and inspected all sensors and cables for damage (which there is none).  I have also switched the TTL-RS-485 board on the MODBUS wing with another (working) TTL-RS-485, which also doesn’t solve the problem.  I can get a perfect CTD record by removing the MODBUS wing.  The strange thing is that I have 6 other sites with identical code that work perfectly.

    I would love to solve this issue without having to install a secondary board.