Question

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?

Answer

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: https://www.segger.com/admin/uploads/productDocs/UM08001_JLink.pdf

 

For more information on Simplicity Commander:

 

  • Knowledge Base Articles
  • 32-bit MCUs