[En-Nut-Discussion] Olimex LTD AVR-JTAG dongle

[Waschk,Kolja]

> Does anyone have any experience with the Olimex LTD AVR-JTAG dongle ?

I'm currently using it with an Ethernut 1.3F board, and avr-gdb/avarice on the
host PC to upload flash contents and for debugging.

You can use the connector as described in

  http://www.ethernut.de/en/jtag/jtagconn.html

with a small modification: the Olimex AVR-JTAG wants to draw its operating
power from the target via Vsupply. Connect both Vsupply and VTref to ISP2.

The Atmel JTAG ICE also works with 3.3V targets; the Olimex AVR-JTAG doesn't,
because it doesn't have the level shifters (and the ATmega16 inside is not the
L version that would run at 3.3V as well - Olimex told me their distributor
didn't have those in stock). That doesn't make a problem if you want to use it
with 5V targets (such as Ethernut) only.

A description how to build a similar JTAG ICE clone can be found on the web
( http://avr.openchip.org/bootice/ ) - but for USD 40, the Olimex device is
really a good buy.

Kolja


-- 
mr. kolja waschk - haubach-39 - 22765 hh - ger
phone +49 40 889130-34 - fax -35 - e-mail s.a.