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3 JTAG Hardware Dongles

Defined: dongle: A small device that plugins into a computer and serves as an adapter .... [snip]

In the OpenOCD case, this generally refers to a small adapater one attaches to your computer via USB or the Parallel Printer Port. The execption being the Zylin ZY1000 which is a small box you attach via an ethernet cable.

3.1 Choosing a Dongle

There are three things you should keep in mind when choosing a dongle.

  1. Voltage What voltage is your target? 1.8, 2.8, 3.3, or 5V? Does your dongle support it?
  2. Connection Printer Ports - Does your computer have one?
  3. Connection Is that long printer bit-bang cable practical?
  4. RTCK Do you require RTCK? Also known as “adaptive clocking”

3.2 Stand alone Systems

ZY1000 See: http://www.zylin.com/zy1000.html Technically, not a dongle, but a standalone box.

3.3 USB FT2232 Based

There are many USB jtag dongles on the market, many of them are based on a chip from “Future Technology Devices International” (FTDI) known as the FTDI FT2232.

See: http://www.ftdichip.com or http://www.ftdichip.com/Products/FT2232H.htm

As of 28/Nov/2008, the following are supported:

3.4 USB JLINK based

There are several OEM versions of the Segger JLINK adapter. It is an example of a micro controller based JTAG adapter, it uses an AT91SAM764 internally.

3.5 USB RLINK based

Raisonance has an adapter called RLink. It exists in a stripped-down form on the STM32 Primer, permanently attached to the JTAG lines. It also exists on the STM32 Primer2, but that is wired for SWD and not JTAG, thus not supported.

3.6 USB Other

3.7 IBM PC Parallel Printer Port Based

The two well known “JTAG Parallel Ports” cables are the Xilnx DLC5 and the MacGraigor Wiggler. There are many clones and variations of these on the market.

3.8 Other...