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The wiki is being retired!

Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to https://doc.coreboot.org/. Contributions welcome!

About this page

This page is maintained by Ward Vandewege (ward at gnu dot org).

About the dongle

The dongle is for sale by Artecgroup, based in Estonia. It costs about EUR 150 (2007-12).

The dongle connects to a computer via USB. It connects to the target via an LPC header.

The dongle comes with free software and full schematics (scroll all the way to the bottom for download links, or click on the CVS: browse link near the top). The host-based software is written in Python, and works just fine under GNU/Linux.

The dongle has 16 MByte of onboard memory, divided in 4 banks of 4 Mbyte each. The 'mode-selection' jumpers allow selection of each bank: 00, 01, 10, 11.

The dongle also has two 16-segment LED displays that can show POST codes.

If you hold the reset button on the dongle, the second LED will show the version of the VHDL you have - currently 03, 04 or 05.

Artecgroup provides a tool to upgrade the VHDL on the dongle that can be run under GNU/Linux (it's a python program). They also provide the binary image for the v5 of the VHDL. Of course all sources are available to build that binary image, but currently proprietary software on Windows is needed to do so. You will need a byteblaster-II cable (which can be purchased http://www.customcircuitsolutions.com/cable.html or http://fpgaguy.110mb.com/, for instance). This tool has only received limited testing, so please be careful and report any problesm to the author.

Using the dongle

Reading from and writing to the dongle

If you use Ubuntu, make sure to uninstall brltty (apt-get remove brltty --purge) before you hook up the dongle; otherwise it will hijack the dongle and you won't be able to talk to it. Brltty is a software braille terminal.

Images are downloaded via USB. With the latest version of the VHDL (v5), it should take about 8 seconds to write a 512KByte image to the dongle.

Here's a command that writes a 512KByte image to the dongle

 ./dongle.py -v -c /dev/ttyUSB0 alix0-1.bin 3584K

The -v parameter makes the command verbose. -c /dev/ttyUSB0 means 'use device /dev/ttyS0'. Alix0-1.bin is the image that is to be written to the dongle (it's a 512KByte file), and 3584K is the offset at which it should be written. Always calculate that number as 4Mbyte - size of your image.

And here's how you can read the image back:

 ./dongle.py -c /dev/ttyUSB0 -r 3670016 512K test2.rom 

The -r parameter indicates 'read', and 3670016 is the offset at which the program should start reading (this is 3584K), for 512K bytes. You can express the offset in decimal (like in this example, in hex with a leading 0x, or in abbreviated decimal - for instance 3584K). Test2.rom is the file the image will be stored in on your computer.

If you actually wrote and read an image, you should now md5sum both files to make sure they are identical.

Booting an ALIX.1C

First of all, you'll need to make a custom cable. The ALIX.1C has a 20-pin header (J16) that can be used to hook up the dongle. The pin layout is documented on page 13 and 14 in the ALIX.1C manual:

1  LCLK0   LPC clock (33 MHz)
2  GND     ground
3  LAD0    LPC data 0
4  GND     ground
5  LAD1    LPC data 1
6  GND     ground
7  LAD2    LPC data 2
8  GND     ground
9  LAD3    LPC data 3
10 GND     ground
11 LFRAME# LPC frame
12 GND     ground
13 PCIRST# reset (active low)
14 NC      reserved
15 ISP     high to use LPC flash, low to use on-board flash, pulled low by resistor
16 VCC     +5V supply
17 GND     ground
18 V3      +3.3V supply
19 SERIRQ  serial interrupt
20 LDRQ#   LPC DMA request

The Artecgroup LPC dongle has a 10-pin LPC dongle that is described in the schematics. This is the pin layout:

2 LAD0
3 LAD1
4 LAD2
5 LAD3
7 R33 GND
10 VCC 3V in

Peter Stuge figured out the correct wiring here and here. This is the wiring diagram:

  Dongle - ALIX.1C

   1 - 13
   2 - 3
   3 - 5
   4 - 7
   5 - 9
   6 - 11
   7 - NC
   8 - 1
   9 - 2/4/6/8/10/12/17 (just pick one)
  10 - NC
     - 15 connected to 18

In the above, pin 7 on the dongle should not be connected to anything on the ALIX.1C. Pin 9 on the dongle should be connected to one of 2/4/6/8/10/12/17 on the ALIX.1C, not all of those pins. Pin 15 and 18 on the ALIX.1C side need to be shorted, but not connected to anything on the dongle side.

Cable length is important - your cable should not be more than a few centimeter long.

The easiest way to make such a cable is to take an old floppy or IDE-40 flat ribbon cable (don't use IDE-80, its wires are much thinner which makes things harder), cut it, and put a 10-pin header on the dongle side.

If you are in the US, you can buy 10-pin headers here (Jameco part number 32492). You might also want to get a crimping tool (Jameco part number 73252).

This is what a finished cable looks like:

Custom ALIX.1C to Artecgroup LPC dongle cable

You can test your cable by booting the ALIX.1C, and then hooking it up to the dongle (using J16 on the ALIX.1C, of course). Now reboot the ALIX.1C board; the LEDs on the dongle should show post codes as the ALIX.1C shuts down and tries to boot. Unless you've prepared the dongle and stored an image into it, the ALIX.1C will not boot. But if you see POST codes on the LEDs, your cable is likely to be good. If not, use a multimeter and make sure it matches the layout above. Also make sure that it is not too long.

Now make sure the dongle is correctly configured:

Jump pin 1/2 on J1. Make sure JMP4 is set to position 1/2 (i.e. NOT to the pins marked as LPC). Make sure that you leave the mode select jumpers in the same position between the writing of the image into the dongle and trying to boot off it.

Now write your image to the top of the memory bank you want to use (see higher). Then disconnect the dongle from your computer, reconnect it, make sure that you have your cable connected to the LPC port on the dongle and J16 on the ALIX.1C, and plug in power to the ALIX.1C. Also hook up a serial port to the ALIX.1C so that you see what happens during boot. If all goes well, you will see post codes on the dongle LEDs as the ALIX.1C boots.

GNU head This work is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or any later version. This work is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.