RS232 Unusual "Framing Error"
I found a copy of a service manual here: https://archive-resources.coleparmer.com/Manual_pdfs/genesys%2020%20service%20manual.pdf

It says:


  
  Ensure the RS232 setup on the GENESYS 20 is set up correctly by
  following these steps:
  
  a. Press the Utility key.
  
  b. Use the down arrow key until you see the RS232 Setup option on the display.  To change any of the settings of the RS232 setup, press CHANGE, then use the up or
  down arrow keys until you getthe correct setting and then press
  ACCEPT.
  
  c. Set Baud Rate for 9600
  
  d. Set Data Bits for 8
  
  e. Set Parity for None
  
  f. Set Stop Bits for 1
  
  g. Set Handshake for CTS/RTS
  
  h. Set Terminator for CR+LF
  
  i. Press the ESC key to go back to the normal menu
  


In particular, I noticed that the recommended handshake is CTS/RTS. Probably worth trying that.

Update: I also found a copy of the operator's manual here: http://photos.labwrench.com/equipmentManuals/1726-1828.pdf