Multiple Modems in a System (for a multi-module Hotspot or Repeater system) Changing the PID on a GMSK Modem running DUTCH*Star firmware Configuring the G4KLX programs

The basic home-brew D-Star compatible simplex Hotspot or full-duplex repeater operating on one band or module is straight-forward.  This is a block diagram of a one-band repeater:

If you want your system to support more than one band or D-Star module, you will need to add another modem and another radio (or pair of radios if full-duplex).  The 2nd modem must be configured to have a different USB Product ID (PID).  Modems running DUTCH*Star firmware can have their PID easily changed from the default of hex 300.

Here's how:

• Get a copy and install the setpid software from the DUTCH*Star website
• Run the program (called nacfg) to change the 2nd or 3rd Modem's PID
• Reconfigure NAWinCFG and NAWinTEST to look for the new PID
• Test the new modem(s) and configure to work with its analog radios
• Change the Repeater software to work with more than one Modem.

Notes: 

• This page assumes you know how to set up a GMSK Modem-based single-module repeater using G4KLX programs.  The information here is how to add a second modem and second set of radios.
• This page also assumes you will do the one-time configuration using the Windows versions of the DUTCH*Star programs. These programs are available to everyone from the DUTCH*Star website.   Some of the programs (NATools and NATest) are also available as executables that will run on 32 bit and 64 bit Linux.  DUTCH*Star, upon request, can also provide executables compiled for the Raspberry Pi ARM processor.

What PID should I choose for the 2nd modem?

The default PID on DUTCH*Star firmware GMSK Modems is hex 300.  When you change the PID on your 2nd modem, you need to pick a PID that is supported by the driver files used by the DUTCH*Star utility programs.  The default files for NATools support 300 (GMSK Node Adapter), 301 (GMSK Node Adapter Delay, as used by the original Satoshi boards), 310 (GMSK DV Adapter), and 320, 322 and 324 (GMSK Node Adapter).  So you can choose 301, 310, 320, 322 and 324 without having to edit the NATools' driver .inf file.  While some of those devices are no longer being used, it is recommended your 2nd modem use 320 and any 3rd modem should use 322.  The following information refers to the 2nd board, but the same procedure will apply to the 3rd Modem, as long as you use a different PID, like 322.

Changing PID on 2nd board:

1. Install the NATools Set PID tool:
   • Get the NATools Set PID tool from www.dutch-star.eu/software/ and save setpid.zip to a known directory
   • Extract the files to a known location
2. To run this command-line program:
   • Open a command line window (used to be called a “DOS Box”) using the Run as administrator feature:
     • Windows icon at bottom left
     • All Programs > Accessories
     • Right-click on Command Prompt and select Run as admin
   • Change directory to where you saved the files extracted from the setpid.zip
   • Type nacfg to run it
   • Enter P (set usb device pid)
   • Enter the new pid (e.g. 320)
   • Program will change the modem’s PID, then fail.
3. To prove it worked, rerun nacfg, passing in the new pid, by typing: nacfg –U 320
4. You can then run NAWinCFG. Go to Tools > Options and change Device PID to 0320, then Close, then Close again. Start NAWinCFG again and it will find the 2nd board and allow you to configure the firmware settings. You’ll have to do all this again, changing PID back to 0300, if you want to change settings on your 1st board.
5. You have to do the same thing if you want to use NAWinTEST on the 2nd board