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Cannot connect to Xevo TQ-S micro, Xevo TQD, or SQD2 using Hyperterminal - WKB9987

Article number: 9987


  • RS232 cable is connected from MS to PC
  • Hyperterminal is started using COM1
  • No arrow cursor (>) appears, only the placemarker (_)
  • System does not respond
  • Tried the alternative port speed setting (See article #2838, Nonsense characters in Hyperterminal Log)


  • Xevo TQ-S micro with new Kontron EPC (PCB SAP part number 700011091)  
  • Xevo TQD with new EPC (PCB SAP part number 700011089)
  • SQ Detector 2 (SQD2) with new EPC (PCB SAP part number 700011089)


The new EPC requires a null modem cable to communicate with the PC via Hyperterminal.
This is due to pins 2 and 3 of the serial port being swapped on PCB 210001013, compared with the old PCB.


  1. Use a male-female null modem cable (RS232 with pins 2 and 3 crossed).  Waters does not spare this cable out.  However, these cables can be easily found online.
  2. Alternatively, a female-female null modem cable with a male-male gender-changing adaptor may be used.
    (The male-male gender-changing adaptor is not currently available as a spare. Please source locally. 
    The female-female null modem cable is SAP part number 8932388-S.)



See this article by National Instruments: The Difference Between a Null Modem and Straight Through Serial Cable

Waters does not currently supply any 9-way, M-M gender changers. We are working to have this item available. When it is available as a spare, the part number will be added to this article.


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