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VersaKit-30xx
3.1 VJTAG-USB Power Supply Considerations and JP1 Header
The VJTAG-USB interface takes power via the USB serial bus; It can be used to provide a 3.3V supply to either the
devboard or the connected target board, provided that the power current consumption does not exceed `~100mA in total.
The JP1 Jumper provides a connection between the VJTAG-USB 3.3V power supply and the target board 3.3V power. If
the target board gets its power supply from an external source, such as a DC adaptor, we recommended removing the
JP1 Jumper.
3.2 Power and Status LEDs
The VJTAG-USB features two green surface mount LEDs indicating the state of the board.
The power LED is connected to the 3.3V supply of the VJTAG-USB. Depending on the state of the USB driver, when the
USB cable is connected to the VJTAG-USB, the power LED may either turn ON or stay OFF. However, when the Versa
Ware JTAG software is activated and the target device is recognized, the power LED will turn on and remain on.
If the USB cable is disconnected from the VJTAG-USB board while the Versa Ware JTAG is idling, when you reconnect
the board, the power LED will remain off until the <Synchronize> button is clicked.
The status LED reports on communication between the Versa Ware JTAG software and the VJTAG-USB board.
Table 3: VJTAB-USB LED Functions
Status LED
Programmer Mode
Off
Versa Ware JTAG Software is
idling: The program in the target
may or may not run.
Sporadic
Indicates that the Versa Ware
blinking
JTAG Software and the VJTAG-
USB board are communicating
Blink
X
On
X
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Debug Mode
Status LED should be ON or blinking
Some operations such as <Restart>, will make both
power and status LEDs ,blink
The target processor device is executing code
The target processor has halted
page 11 of 28
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