Electronics > Electronics

ft232r problems.

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JonHylands:
One thing to try is plug it into a Windows XP machine - the drivers for that chipset are either included, or easy to find, and it works nicely.

That will at least sort out if it is a driver issue versus a hardware issue...

- Jon

Admin:
So looking at the offered connection diagrams (such as on pg 23 of the datasheet), but they dont use the reset pin . . . as a matter of fact they never do in examples . . . and Im just curious why you do this wierd voltage divider from the USB power to send 3.57V to the reset pin . . . why not just tie it to VCCIO like the datasheet says?

ignore this comment if Im being dumb, Ive never used this chip before . . . ;D


And unrelated to your problem, but Im just curious why you decided not to use the 5V from USB to power the board?

JonHylands:
Yeah, my setup is a lot simpler than dunks - I power the entire setup off the USB bus.

- Jon

dunk:

--- Quote ---So looking at the offered connection diagrams (such as on pg 23 of the datasheet), but they dont use the reset pin . . . as a matter of fact they never do in examples . . . and Im just curious why you do this wierd voltage divider from the USB power to send 3.57V to the reset pin . . . why not just tie it to VCCIO like the datasheet says?
--- End quote ---
so i went with device power rather than USB power for no particular reason. just seemed like the right call at the time as there is allready a perfectly good 5V source elsewhere in the circuit. (it's illustrated on p20 of the datasheet.)
the idea being that the FT232 doesn't come out of reset until it's plugged into the USB port so everything initialises properly. (or not in my module's case...)

i have noted though that Jon had better luck than me using this chip in bus powered mode. i'll try building a version that way round.


--- Quote ---And unrelated to your problem, but Im just curious why you decided not to use the 5V from USB to power the board?
--- End quote ---
so i'm going to have several AVRs, servos, motor controllers, sensors, bells and whistles on this project.
(it's my latest robot's interface boards finally being built. drum roll please...)
the combined load would be far too much current for the USB port on my embedded controller.


--- Quote ---One thing to try is plug it into a Windows XP machine - the drivers for that chipset are either included, or easy to find, and it works nicely.
--- End quote ---
so i'm planning on bringing the module along to work tomorrow to see if i can borrow a windows machine somewhere.
we usually pick on windows users at work but they do have their uses....

dunk.

dunk:
ok, i feel dumb.
so while rewiring the board to take power form the USB port (which made no difference) i decided to give all the contacts on the FT232 chip a good roasting with my soldering iron.
after that the whole thing works fine.
so, obviously either a bad connection or a solder bridge underneath the chip. (but not one bad enough for me to find with a multimeter.)
either way, it works now.

so, happy days. dunk's next robot is one step closer...

dunk.
(new to surface mount components.)
((thanks Jon and Admin for the suggestions and moral support.))

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