"OK, it needs a bootloader (the..." <- > <@thejpster:matrix.org> OK, it needs a bootloader (the ROM can't do it). You could ask in #stm32-rs:matrix.org but personally I've never needed external flash on an STM32. They do parts with *loads* of flash so I just pick those! > > What software are you driving the ST-Link with? probe-rs-cli? openocd? > So, I've seen this done before in C. I think a common driver is if you want the H7 's speed etc, but are minimizing cost. The low-flash H7 s + external flash comes out much cheaper than a high-flash H7. I don't know how the firmware-on-external works, but it's doable