This is mostly a post to help people who try to google this later since I couldn't find anything. If you look at AN2606 table 197, it lists the minimum startup time for the bootloader on a bunch of different STM32 microcontrollers. For some reason, just two MCUs have "NA" listed including the chip I'm currently working with - the STM32L4R. So if anyone is wondering, my testing has shown that it takes ~90ms from reset/powerup to when the chip will ACK the 0x7F message on USART.
I am curious though, does anyone know why no time is listed for these chips?
