Lammert Bies – Computer Interfacing

db9_null_dumb

Information about computers and how to interface them to all kind of equipment. Both software and hardware help is available. – Lammert Bies

Lammert Bies – Computer Interfacing

  • RS-232 specs
  • RS-485 information
  • The serial UART
  • USB interface
  • Modbus interface
  • Unitronics RJ11

Simple null modem without handshaking

db9_null_dumb

“only the data lines and signal ground are cross connected in the null modem communication cable. All other pins have no connection. An example of such a null modem cable without handshaking can be seen in the figure below.”

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