[avr-chat] FTDI232 chips & Missing data

[Matt.VanDeWerken]

Hi all:

Not strictly AVR, but since I've got these little babies connected to my
AVR there is a connection there (no pun intended).

We're having trouble when sending large-ish amounts of data from an AVR
serial port to a windows ce embedded PC (PIII-1GHz) via an FTDI232
USB-serial bridge. There are no such troubles when a direct serial
connection is used to a windows XP host.

The baud rate is 38400, so I wouldn't have thought that the PIII would
have any trouble keeping up, but there is missing data when we try to
send more than 256 bytes down the line. The data is always missing at
the 256 byte mark, which indicates to me a buffer overrun problem. There
appear to be no troubles when we run at 9600 baud, but we need to run at
the faster speed, and our packet size can be as small as 412 bytes (yes,
412 not 512) due to the nature of the data. We could split the data
further but I'd really rather solve the cause issue.

Has anyone on the list encountered and solved this problem before,
either by tweaking the FTDI driver, or by adding flow control, or
something else.

Cheers,
Matthew van de Werken - Electronics Engineer
CSIRO E&M - Rock Mass Characterisation - 1 Technology Court - Pullenvale
- 4069
p: (07) 3327 4142 * f: (07) 3327 4455 * e: address@hidden
"We do not inherit the earth from our ancestors, we borrow it from our
children." 
-- Native American Proverb