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>from the help line
>Hi, could you send me the schematic for your FTDI board? I have the ARMMite pro
and I want to do bidirectional serial communication. Using the FTDI board in
your starter kit, I am able to program the chip and do bidirectional serial
communication. However, using the Sparkfun FTDI board, I am able to program the
chip, but I am not able to receive serial messages sent by the chip. I\'m trying
to figure out what the difference is between your FTDI board and Sparkfun\'s
FTDI board, so if you could send me the schematic that would be great. Or, if
you know the solution to this problem, that would be great too. Thanks,

The main difference is on ours the RTS output (from USB chip) is connected to
control whether the ARM boots into the bootloader or the application code at
reset. SparkFun's connects that to CTS going to the USB chip, but unless you
are using hardware handshaking that should not be an issue.

Another possibility is power. We recommend using the 5V SparkFun dongle, not
the 3.3V version. At 3.3V the power to the ARM would be aroung 2.5 V or so,
enough to run some chips, but very marginal. During programming the current
drawn by the ARM actually drops from the normal 40-50 mA to less than 20. So if
your are powering the PRO from the USB derived 3.3V, that may be the issue.

A schematic of the USB dongle will be posted in the files section.

I don't suppose the USB adapter thingie that comes with ARMWeb eval kit will
work with any of the other boards? I realize it has two sets of header pins,
but wouldn't the RS-232 side be the same?


-MM

Hmm, it looks like the tx/rx/3.3/gnd connector on the end is not pin-compatible
with anything else, however, the FT232R connector should work wherever a
SparkFun or FTDI can be connected (e.g., ARMmite Pro), correct?

-MM

some background

The original USB connection for ARMweb used a breakout board from SparkFun (we
didn't need to re-invent the wheel). But about a year later SparkFun redid that
board and changed the connector spacing.

So we ended up having to build our own anyway, and it shares the same PCB with
different connector stuffing for the ARMweb, ARMmite PRO and an OEM board for
another customer.

Ok, cool... The USB adapter that came with my ARMWeb eval kit has 2 headers
oriented at 90 degrees to each other, one has the usual set for a serial
connection, the other is labeled FT232R. Will either side work independently?

It looks like all I need to do is make a cable to rearrange the pins, to use
this one to connect to a Pro/SuperPro?

-MM

> It looks like all I need to do is make a cable to rearrange the pins, to use
this one to connect to a Pro/SuperPro?

Yes, for more details

if the board is green, its the Coridium version, schematics are in the Program
Files/Coridium/Schematics/USBdongle.pdf

if the board is red its the sparkFun verison, schematics on their website.

Very cool, thanks!


-MM

Just in case anyone else wants to do this, this is the pin-out:

SuperPRO USB Dongle
J5 Pin 1 to J5 Pin 3
J5 Pin 2 to J4 Pin 2
J5 Pin 3 to J4 Pin 3
J5 Pin 4 to J4 Pin 4
J5 Pin 5 to J5 Pin 4
J5 Pin 6 to J4 Pin 1

On the USB, connector J4 is the one that has pins labeled "3.3V", "RXD", "TXD"
and "GND". (Pin 1 is GND.) While holding the board so that J4 pin 1 is in the
lower left corner, J5 pin 1 is on the left end of J5.

I also uploaded a schematic diagram to the files section.


-MM