- Send notifications to ExtUI for M0/M1
- wait_for_user can be non-volatile (not changed by interrupt)
C / C++ compilers don't optimize away reads of non-volatile variables when a function call is used between accesses, because *any* variable could be changed by the function call. Since `wait_for_user` can't be changed without a function call, it should be non-volatile so the compiler can optimize away cases where it is read more than once without an intervening function call.
- Ensure `MarlinUI:get_progress` is defined for `ExtUI`.
- Fix for `BACKLASH_SMOOTHING` with small segments.
`BACKLASH_SMOOTHING` with extremely small segments failed to fully correct due to the correction factor being rounded down. Rounding up ensures the entire backlash will converge to zero even for small segments.
- Add pinout for the beta revision `EINSY_RETRO`.
- Update soft endstops with tool offsets (for toolchange et. al. move clamping) (#12568)
- The `sdcard.transfer_port` variable is Marlin's internal serial port index, not the physical serial port number.
- Added packet number to "ok" response so hosts don't need to wait for the ACK.
- Renamed feature to `BINARY_FILE_TRANSFER`, as the speed up is only consequential to the ability to transfer binaries over serial.