The EFM32 and EFR32 Wireless MCU Series 1 devices support JTAG chaining.  What options do I have to make use of this capability in my development/production environment?


The Starter Kits (STK) and Wireless Starter Kits (WSTK) we provide for these devices implement an on-board SEGGER J-Link debugger/programmer that supports JTAG chaining.


Simplicity Studio does not currently support JTAG chaining.  However, a tool available within Studio - Simplicity Commander (more information below) - does provide JTAG chaining support via the command-line interface.


The following Simplicity Commander command line options must be used when accessing a device in a JTAG scan chain:



  --tif <SWD|JTAG|C2>                  Target debug interface.
  --irpre <IR length>                  JTAG: Total length of instruction
                                       registers of all devices closer to TDI
                                       than the addressed ARM device.
  --drpre <Data bits>                  JTAG: Total number of data bits closer
                                       to TDI than the addressed ARM device.



These options are passed on to the J-Link DLL, and are documented in more detail in the J-Link User Guide:


For more information on Simplicity Commander:


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