Questions about USB development

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Hi all

Been reading some posts, have lots of confusion. I need a (cheap) low speed  
USB programmable microcontroller development board, plus (re)flashable
chips to go with it. It must
A) Be cheap
B) support ASM coding
C) Be useable with Windows HID drivers
D) both be useable as a development kit and a chip flasher
E) be able to develop "low-speed" usb chips

The closest I've found is
However, I don't think any of the products match my desires. Please help.
Thanks in Advance


Re: Questions about USB development
What is wrong with the DLP245PL? It uses drivers and USB chip from FTDI
( can be reprogrammed or used as is for lots of I/O pins.

Tom Woodrow

DarkKobold wrote:
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Re: Questions about USB development

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Thanks for the response. From what I saw on the DLP245PL chip, it is for
full speed chip development. From my understanding, this is not good for
keyboards, mice, and in my case, joysticks. Is it possible to develop low
speed for the DLP chip?

Re: Questions about USB development

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I don't know anything about the DLP245PL, but there is nothing wrong
with "full speed" USB keyboards, mice, and joysticks.  The device type
and its capabilities are detemined by the message content, not its
baud rate.  Low speed is a cost issue: it lets devices with low
throughput requirements (like keyboards etc.) shave a few pennies in
hardware cost.

For example, several years ago I developed a keyboard and mouse
simulator for a test system (i.e., a device that lets a test system
provide keyboard and mouse input to a target system through the
target's USB port).  We used AnchorChips (now Cypress) EZ-USB, which
is full speed device.  Works well.


Change is inevitable, progress is not.

Re: Questions about USB development
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is easy to use and cheap. It contains a excellent description of the USB
functionality what saves you many time in reading the USB standard. The
kit comes with custom windows drivers and is not a HID, but if you tackle the
report descriptor it should be easy to modify the firmware (source
available) for your HID needs. Therefore the descriptor tool DT is
recommended. My HID code completely written in C is now about 600 bytes.

Re: Questions about USB development

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Thanks for the response! This by far is the best for me, I think. It
matches all of my requests/requirements. However, the US distributor
seems... shady at best. Also, the fact that the site is a foreign company
seems like support would be nil. Is it worth the risk? Also, would you be
willing to post your HID code, or direct me towards sample code? thanks!

Re: Questions about USB development
my HID code for the PC based on the example of Jan Axelson - See

my HID code for the target based on the flow diagramms found in the USB
book of the Franzis Verlag (Germany)

Re: Questions about USB development (Lewin A.R.W. Edwards) wrote in

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Thank you for your response! I had looked at these before... I would
really like to use this suggested board... But unforntunately, it appears
the only thing it is used for is Full Speed USB application. Since my
base code is cypress, this would be ideal, except that the original line
my sample code is based on is a different cypress line all together. It
is my understanding that low/full speed USB are NOT interchangeable.
Also, it would make coding transformation difficult. Maybe I'm wrong tho.
I'm new to the whole imbedded controller world.

Re: Questions about USB development
If you do decide to go down the Cypress EZ-USB route, I have a barely
used Cypress EZ-USB FX2 developer kit which I no longer need.

Cypress describe this kit as below:

 Developer Kit: CY3681 EZ-USB FX2 Development Kit, Apr 21, 2003
 The kit includes the following: EZ-USB Development Board with
 128AC, peripheral Board for prototyping, USB cable, and an RS-232
9-pin to 9-
 pin cable.

Cost me £450 in the UK, I'll let it go for about £200, maybe less.

Thanks, pete_moretonATyahooDOTcom

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