User manual

communication with targets running at any voltage between 1.8 and 5.5V
Note that the target voltage must be applied to pin 2 on the ISP header for the AVR Dragons level converters.
JTAG Header(mounted):
The 10-pin JTAG header is a standard pinout JTAG connector. When connecting the AVR Dragon JTAG header to an external target, the
signals are level converted to match the target board voltage. This is done automatically. Please note that the AVR Dragon will not power
the target through the JTAG interface. The target needs to be powered through a dedicated powersupply. (or by powering it using the
VCC connector (5.0V max 300mA). AVR Dragon needs to sense the target voltage on pin 4 on the JTAG connector.
Pin Signal I/O Description
1 TCK Output Test Clock, clock signal from AVR Dragon to
target JTAG port
2GND - Ground
3 TDO Input Test Data Output, data signal from target
JTAG port to AVR Dragon
4 VTref Input Target reference voltage. VDD from target
used to control level-converter
5 TMS Output Test Mode Select, mode select signal from
AVR Dragon to target JTAG port
6 nSRST In/Out-put Open collector output from adapter to the
target system reset. This pin is also an
input to the adapter so that the reset
initiated on the target may be reported to
the AVR Dragon
7 - - Not connected
8
--Not Connected
9 TDI Output Test Data Input, data signal from AVR
DragoI to target JTAG port
10 GND - Ground
HV_PROG Header (not mounted):
The HV_PROG connector contains all signal required to do HVSP or PP programming. The signals on this connector is not level-converted,
and should only be connected to the EXPAND connector on the AVR Dragon. You could damage both your target and the AVR Dragon if
you try to do HVSP or PP on an external target board. The signal levels on the HV_PROG header are 5V.