Loading/upgrading bootloader via serial port

Topics: Developer Forum, Project Management Forum, User Forum
Oct 2, 2007 at 3:47 PM
Edited Oct 6, 2007 at 7:47 PM
Several people have reported communication errors during loading and/or upgrading the bootloader via the FFUART or STUART.
This is usually the result of the host PC "overdriving" the Gumstix's serial port. The FFUART and STUART on the Gumstix do not have hardware handshake lines so it is very easy to overrun the input buffer especially if you are using a very fast Host PC.
A simple solution is to "pace" the TX channel from the PC. Hyperterminal has this ability if you look in the Settings->ASCII setup->ASCII sending properties you will see a setting for "character delay"and "Line delay". Experment with these setting but I would guess 1 or 2ms would be enought time to prevent overrun of the Gumstix UART when running at 115000 baud.