rusefi.com

My latest Frankenso board has three spots for mini-USB ports. Two of them are populated with a connector.
One is labeled TTL and when I plug this into my computer, a friendly little green LED comes on. Nothing else seems to happen though. One is labeled PROG, but not populated. (Even though I believe it's populated on another board I was working on and it didn't seem to do much).
Last but not least, there's one off to the side of the brainboard. In the vicinity of the SD-card. This one doesn't seem to do anything at all either.

So, my question: What's up with these? They must have a purpose. My suspicion is, they are not really USB at all- are they?

I may remember this wrong but my bad memory reminds me that one is fti 232, another is initial programming from a fresh chip then the third was just a dead prototype. The prog doesn't normally get used as must get Discovery boards which already have a boot loader.

PROG is to PROGramm native smt32 chip if it's right on Frankenso - not the case usually.

test USB module in the middle was just a test footprint and it's removed from future revisions of the board. We were testing some footprint modification.

165) RESOLVED IN R0.5.2 remove test_module1501 to reduce confusion. Module was a test footprint, combining multiple other footprints into one.

Now, TTL should be a USB serial port. TTL is connected to FT232 usb/ttl driver, your OS was supposed to install FT232 drivers - there is a link to that driver on https://rusefi.com/wiki/index.php?title=Manual:Software:User/en see http://www.ftdichip.com/Drivers/VCP.htm

I'd forgotten about that driver. TTL works now.
Why only 38400 baud though?

There is a setting to adjust somewhere

Found it - it wasn't even all that well hidden