it works! got it running tonight and wanted to share.
the code is nothing fancy
excuse all the printf's i use those for debugging, i use Putty connected at 115200 8-N-1 via my usb
i'm using usart3 for the printf to work, along with the _write() function at the bottom (won't work without it)
i have all kinds of timers enabled, but this demo is using only ONE channel of TIM4
(i have 18 motors i will be controlling on this robot so i have work to do haha)
excuse the code it's not very good. i'm somewhat of a newbie old guy, haven't been programming in C in about 25 years, and also hadn't used an o-scope
i'm using a Nucleo-F746ZG (STM32F746ZG)