Stage 2 – Power and pin mapping options

You will now see the Project Setup Wizard, which you can use to configure the JTAG interface on your XJLink.

The Pin Mapping Tab will be selected. This allows you to specify how the pins on the XJLink should be used, and select whether to power the circuit through the USB connection.

N.B. The preset XJDemo4 pin mapping for XJLink2 uses the XJLink2's capability to supply power to a circuit. This is not recommended for test systems due to the very limited power that can be supplied. The functionality is not present on XJLink-PF series controllers.

The configurable pin mapping of the XJLink gives great flexibility, but for this tutorial, using the XJDemo board, you can use one of the predefined pin mapping options. With the XJLink2 the XJDemo board is powered through the XJLink's USB connection. If you are using an XJLink-PFxx controller the USB connection to the demo board adapter will provide power to the board, and the XJLink-PFxx controller will switch that power on and off as required during tests. To set up this configuration:

If you are using the XJLink2, after clicking Next you will see a pop-up warning you that powering your circuit in this way may damage your USB interface. Because the XJDemo board is designed to use USB power, it is safe to do this:

The XJLink2 pin mapping has some pins marked as Soft Ground. This designates a pin which is driven low by the XJLink, and which is driven through a lower impedance than a normal low signal. However, it is not such a good ground connection as Pin 10 or Pin 20 (Hard Ground).