- cheap way to develop a USB device?
- Posted by yong on December 15th, 2003
What is the cheapest way to develop a USB device? The Cygnal F32x
seems good for its on chip USB controller. But it needs the Keil tools
which is expensive. Is there any USB tools(hardware/software) exsisted
which is under $500 for 8 bit microcontroller like 8051,PIC, or AVR?
For very low volume, I need low price development tools.
- Posted by CBarn24050 on December 15th, 2003
hi look up FT232BM
- Posted by Bob Stephens on December 15th, 2003
On 15 Dec 2003 10:55:36 -0800, yong wrote:
The Cygnal F32x development kit comes with an evaluation version of the
Keil development tools limited to 4K of code. Also includes simple USB
example code.
Bob
- Posted by Adam Braun on December 15th, 2003
"yong" <yqin_99@yahoo.com> wrote in message
news:be3c7875.0312151055.3371c868@posting.google.c om...
The Cygnal part is a good option and it does not require the Keil compiler.
I have worked with the part using SDCC and it's been great for me. The only
strange thing that I have run into is that the Cygnal debugger and the
compiler have a different view of which "endianess" is used for the part.
If you can see past that, it's fine.
That said, getting a USB Vendor Id value could present a big hurdle to your
$500 target.
Adam
- Posted by Meindert Sprang on December 15th, 2003
"Adam Braun" <a.braun@comcast.net.nospam> wrote in message
news:RroDb.58213$8y1.229227@attbi_s52...
Another good reason to go for the FTDI chips. It's a single chip
ready-cooked solution. No worries about USB code and you get Product ID's
for free from FTDI. So you use FTDI's Vendor ID and a Product ID which they
assign to you upon request (issued in blocks of four). They provide a driver
set that can be tailored to your product by putting the right strings in the
INF files and by programming the right flags and values in the EEPROM of the
chip. And they provide the tools for that too.
Meindert
- Posted by Adam Braun on December 15th, 2003
"Meindert Sprang" <mhsprang@NOcustomSPAMware.nl> wrote in message
news:3fde3716$1@news.nb.nu...
The FTDI chip does provide all of these things and it is a good solution if
you are looking to use the USB connection only as a custom data channel to a
specific application. If you are only working with an embedded host, then
this can be a good solution.
However, if you intend for your device to connect to the system as a
specific device type (ie. mass storage, HID, etc.), it is generally MUCH
easier to handle the custom firmware development and use standard system
drivers then to try to connect the FTDI interface through the standard
system stack on each of the different operating systems.
Adam
- Posted by Mike Turco on December 17th, 2003
"yong" <yqin_99@yahoo.com> wrote in message
news:be3c7875.0312151055.3371c868@posting.google.c om...
Develop a serial device and then use a serial-to-usb converter. -- Mike
- Posted by Steve Calfee on March 5th, 2004
On 15 Dec 2003 10:55:36 -0800, yqin_99@yahoo.com (yong) wrote:
The cheapest way is to buy a keyspan usb to serial device about $39.
It contains a cypress ezusb chip, which gets its code downloaded when
it is plugged in.
see http://people.omnigroup.com/wiml/soft/pic/keyspan.html for a
complete how-to. I have not tried it yet myself.
HTH ~Steve
- Posted by Gerhard v d Berg on March 5th, 2004
"Steve Calfee" <stevecalfee@hotmail.com> wrote in message
news:dbnf409kjrf35kc6ih1ehv4dp6das5icga@4ax.com...
It depends on product volume and requirements.
We used the DLP-USB245 module with great success.
You can also buy the chips FT245BM.
See http://www.dlpdesign.com/usb/usb245.html module +-$25
and http://www.ftdichip.com/FTProduct.htm Chip +-$5
The FT245 has an 8-bit paralel interface and the FT232 a serial interface.
No USB programming required. Device drivers are free of charge.
Gerhard
see
- Posted by Bob Stephens on March 5th, 2004
On Fri, 5 Mar 2004 16:00:47 +0200, Gerhard v d Berg wrote:
What OS's do they support?
Bob
- Posted by Meindert Sprang on March 5th, 2004
"Bob Stephens" <stephensyomamadigital@earthlink.net> wrote in message
news:1cshny7apnz4n.gio6bwzbbp9w.dlg@40tude.net...
Windows 98, ME, 2000, XP.
Max OS8/9, OSX
Linux (standard in every kernel after 2.2, I believe).
Meindert
- Posted by Adam Braun on March 5th, 2004
"Steve Calfee" <stevecalfee@hotmail.com> wrote in message
news:dbnf409kjrf35kc6ih1ehv4dp6das5icga@4ax.com...
The Cygnal F32x device doesn't require the keil tools to use. It is
basically an 8051 core so you can use any 8051 tool chain with. The
examples that Cygnal provides are based on the keil toolset, but I
personally have programmed the part using other toolsets.
- Posted by Tsvetan Usunov on March 6th, 2004
We use FT232 in one of our products, the issue we have with it is that
out of 10 plugs in/out it fails operationg at least once.
First we thought that it's something with the Windows USB drivers, but
then we found that when it fails the FT232 chip have no oscillations
i.e. it's pure hardware problem.
The problem is not very anoying as in case of device fail you simple
unplug and plug again and it works, but this left the impression in
the customers that complete device is not very reliable.
Did you experienced something like this?
Best regards
Tsvetan
---
PCB prototypes for $26 at http://run.to/pcb
(http://www.olimex.com/pcb)
Development boards for ARM, AVR, PIC, and MSP430
(http://www.olimex.com/dev)
- Posted by Meindert Sprang on March 6th, 2004
"Tsvetan Usunov" <tusunov@my-deja.com> wrote in message
news:dd52331e.0403052311.53ebf7a@posting.google.co m...
I have never experienced this. We sold about 750 units of our product using
this chip and have never experienced this. I'd say it is a design/PCB layout
fault.
Meindert
- Posted by Tsvetan Usunov on March 7th, 2004
the crystal is placed next to IC, with very short tracks, surrounded
by GND
where is our failt? we did such routing to hundreds of other designs
that you didn't experienced such problem may be just that us used
another batch of ICs or something else.
Sometimes ICs don't behave as per their datasheets you know 
Two months ago we had complain for our PIC-MCP programmer that "it
doesn't connect" to MPLAB - it was strange as we do 100% control to
all our devices, so we called them back for review. We received boards
and they worked at our place! But after more extensive tests we found
that these two devices doesn't work if the ambient temperature is
under 20 C ! It seems like the WDT is ticking with much more short
period than expected - 4 ms instead 18 ms as per datasheets.
We spent two weeks in debugging exactly the tese two devices, but the
problem was that there was not quite repeatable pattern i.e. devices
sometimes worked with hours then the other day stopped work, this was
absolutely crazy as thousands of such devices were working without any
complain by our customers.
We were 1000% sure that this is some glitch in our code, then after
two weeks of banging our heads to the wall, we though that may be from
the PIC and read PIC16F876A errata sheets. There Microchips states
that for mask revision 02 some of the PIC16F876A may not execute code
right if clocked at more than 4Mhz!
They suggest the following test procedure if something goes wrong:
program 100 PICs and test them if they all behave the same the problem
is in your code, if some of them behave different th eproblem is in
the PICs so we learned this the hard way.
These PICs were just from this early revision and out of 100 pcs lot
(we track we bought) only 2 were showing this.
Best regards
Tsvetan
---
PCB prototypes for $26 at http://run.to/pcb
(http://www.olimex.com/pcb)
Development boards for ARM, AVR, PIC, and MSP430
(http://www.olimex.com/dev)
- Posted by Meindert Sprang on March 7th, 2004
"Tsvetan Usunov" <tusunov@my-deja.com> wrote in message
news:dd52331e.0403070246.39fb6845@posting.google.c om...
Is that groundplane directly connected to the capactirors and pin 29?
What value of caps did you use (most made error is a too small value)?
I know.
Meindert
