stm32f7: Add nucleo-f767zi example

[antonblanchard]

[karlp]

I'm not really all that interested in adding more copy pasta examples to this repo, it's hard enough to manage as it is. While I do see that there's no f7 example in this repo yet, I don't want to just have a plain copy example. I'll leave it open for people to find if they're looking.

[bm16ton]

It would be super great to get sum f7 examples. I know im far beneath you guys in skills and understanding. But stm32f7s uses i2c v2 and i cannot seem to find any examples for that. I would love to see a v1 example and a v2 example for the same firmware. You guys are my heros and i know my place, an arduino example combiner like myself has no leg to stand on. Ive ported the i2c-star (usb-2-i2c firmware) to a couple diff f4s and basic silly stuff like that but cannot make ground with the f7s. The datasheet for my various f7s lack i2c info (well for a fool like me). After the datasheets didnt mention trise and a quick grep of the stm arduino files for trise shows in all the familys except f7s so im guessing they use a different clock/timer setup. The f767 diy terminal emulator firmware uses unicore-mx and an eeprom and it seems to setup the i2c using timingr presc/scll/sclh/sdadel/scldel. Am i correct? Do i remove all the old setup trise/ccr stuff and use timingr? The calls i2c-star uses was ddeprecated in v2 so i search a lot for any examples for v2 and havent had any luck. I know unicore-mx didnt goto v2 and still has the deprecated functions.they seem like a mess with far fewer commits (ironic cuz commit frequency was motivation for the fork). Also just an fyi out of the few i2c examples for other stm32 familys the comments around the i2c setup contradict each other. So for us old fools who got into programming after the age of 40 examples are a very big deal, and comments too. Thank you for your time, if anyone has any links or info on i2c on f7s or examples (ie v2 vs v1 and setup) that would be incredible!