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J-Link/J-Trace Adapter

The J-Link/J-Trace Adapter section shows information about your debugger adapter. The debug port can be configured, the communication speed set, and information about the adapter are shown.

Adapter attributes
  • SN: — displays the identification number of the adapter. If more than one adapter is connected, you can choose the adapter from the drop-down list. The selected adapter will be used for all actions, including downloading, debugging, and tracing.
  • USB# — displays the USB port-number of the connected adapter. J-Link/J-Trace adapters are also identified through the USB port number, which rank from 0..3. The adapter can be allocated to another USB port through this drop-down list. Select a new number and follow the instructions on the screen.
  • Device, HW, FW, and dll — these fields show the driver version installed, the name, hardware, firmware, and dll version of the selected J-Link/J-Trace adapter.
  • Port: — sets the debug mode. You can switch between JTAG and Serial Wire (SW) mode. Serial Wire mode must be supported by both the debug adapter and the target device.
  • Max Clock: — sets the debug connection speed. If debugging is not working properly, manually reduce the JTAG or Serial Wire debugging speed here.
  • Auto Clk: — use this button to detect the supported maximum speed.

Some applications require to start with a lower JTAG Clock from RESET and have to switch to higher clock rates when debugging. Use the VTREG DEBUG_CLOCK to alter the clock rate from scripts.

/*-------------------------------------------------------------------------
  The function sets the JTAG Debug Clock to 2MHz
  after the Main Clock has been enabled and selected.
-------------------------------------------------------------------------*/
FUNC void setJTAGClock()  {
  enableMainClock();         // add your code to switch on the Main Clock

  DEBUG_CLOCK = 2000000;     // Set JTAG Debug Clock to 2MHz
  _sleep_(10);

  enableMainPLL();           // add your code to enable the main PLL
  _sleep_(100);
}
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