Ethernut Home Hardware Firmware Tools Download Community
Suchen | Impressum | English

AVR Programming Adapters

The ATmega128 used on Ethernut 1 and 2 provides to interfaces for programming the firmware into the non-volatile FLASH memory, SPI and JTAG. Unfortunately Atmel decided to use the same connector for both interfaces, a 10-pin boxed header. Even worse, power and ground lines are located on different pins.

Attaching an SPI programmer to the JTAG connector or vice versa will at least blow the fuse on Ethernut 2 and may cause more damage on Ethernut 1, which isn't protected with a fuse.

Click here for detailed information about In-System-Programming of AVR Microcontrollers.

On Ethernut 3, the CPU is an ARM7TDMI, which requires a different firmware for the JTAG programming adapter.

SP Duo

The SP Duo Programming Adapter for AVR Microcontrollers is a commercial product, which has been developed by Embedded Creations. It can be used with Ethernut 1 and 2 as well as most other AVR based boards and connects to a serial RS232 port on the PC. The firmware is protected, but upgrading is possible via encrypted files. It supports both, an SPI and a JTAG target connector. For the PC software it looks like an STK500 compatible SPI programmer. Thus, JTAG debugging is not supported. Click here for more information about the SP Duo.

egnite currently ships all Ethernut Starterkits with the SP Duo included.

SP Duo attached to Ethernut 2.1 Rev-B.


The Turtelizer Programming Adapter is based on the SP Duo Hardware, but its firmware had been replaced by an Open Source JTAG Programming Utility for the ARM7TDMI. It can be used with Ethernut 3 Boards. Like the SP Duo, it is attached to one of the serial ports on the PC.

The project of the programming tool including the Turtelizer firmware is named JTAG-O-MAT and is hosted at SourceForge.

Additional information about using the JTAG-O-MAT / Turtelizer Combo with Ethernut 3 is available here

Turtelizer 2

Click here for more information about this brand new device.


The SIPS is an STK500 compatible programming adapter. Its firmware and the hardware design are Open Source. Click here for a detailed description of this adapter. It additionally presents a lot of general information about AVR device programming. Valuable information about fuse programming is available when following this link.

SISP attached to Ethernut 1.3 Rev-G.


The ATJTAGICE is a product of Atmel.

ATJTAGICE attached to Ethernut 1.3 Rev-G.

ATJTAGICE attached to Ethernut 2.1 Rev-B.

This helpful cable comes with the ATJTAGICE.