Notes on BrainTechnology Boards
While I've not used this board, I have received the following comments that
may be of help (comments have been paraphrased from original emails).
Goetz Bock [bock * blacknet_de], (update October 10, 2002)
The v1.2 board is still missing the resistor for reenumeration (R4, 1k5Ohms,
worth 10cent, bug0) but there are two more bugs:
bug1: the serial eeprom has the i2c ID 0, and the EzUSB chip will not
recognize it as requiring 2 byte addressing. That will not allow one
to install any firmware into the eeprom.
bug2: the i2c eeprom can not be disconnected. That is no problem, because of
bug1, but the addressing problem can be fixed by cutting one "wire"
and adding another smd resistor (R6: 10k).
Kai of Braintechnologies was quite helpfull. While it took some time to
get a response, he offers the following: when specified in the order he
will add/move the problematic resistors free of charge. He sent me the
missing resistors, but I moved R9 to R4 and reenumeration works. The
missing resitor for R6 should arrive tomorrow, then the eeprom will
work, too :-).
So ask for the two resistors and you will get a beautifull, small and
reasonable priced EzUSB devellopment board from Germany (no additional
Tax/Customs for EU users).
Jens Kilian [jjk * acm_org], (update March 06, 2002)
has successfully downloaded the board located here.
Here are the comments from Jens on using the board (I'm including the
comments since I have no experience with the board myself and the
comments may be a time saver for others):
It's a tiny board without any frills, except for 8K of EEPROM.
The producer recommends that it's used with a Windows-based software
package (yuck); the labeling on the board is confusing unless you know
that (the ports are labeled as "address" and "data" buses, in reality they're
just PC and PB of the AN2131SC).
I've successfully used the EZUSB2131 driver to download stuff to the
board. There is one major problem: a missing resistor (space provided, but not
used) which connects the AN2131's DISCON# line to the USB; as a result, the
board can't disconnect, and the "re-numeration" doesn't work. This is not
a problem for me (I don't have any other devices on the USB, and I can
just "rmmod" the UHCI driver and restart it), but may be a serious PITA to
others. I expect that this problem will go away when the AN2131 boots from the
Except for the confusing labels and the DISCON# problem, this is a nice
product (tiny, good quality). The price (incl. tax and shipping)
was about EUR 80.