MACH ETH - User Manual
MACH SYSTEMS s.r.o.
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device restart, second for accessing the USB bootloader and third for accessing the Ethernet
bootloader.
Figure 8 HTTP interface
5.3
System Bootloader
The STM32H7 MCU contains a system bootloader which is pre-programmed in ROM during
manufacture. The system bootloader supports USB, it does not support flashing over CAN bus or
RS232. If the possibility to upload a firmware over CAN bus is needed, the OpenBLT bootloader
described in [2] can be used.
It should be noted that when the device enters the system bootloader whilst USB is connected, the
device can then be flashed over USB
only
. If the user wants to flash the device over RS-232, he has to
either power the device over external power pins (see Option 1 in 4.2) or he has to make sure USB
data lines are not connected. This is the limitation of the system bootloader.
5.4
Ethernet bootloader
With Ethernet bootloader, new firmware can be easily uploaded to the device with only a web
browser. No additional software is needed. Recommended web browser for firmware upload is
Google Chrome. After entering the Ethernet bootloader (see 5.5) the page in Figure 9 Ethernet
bootloader is shown. Users can select a file with firmware and upload it, switch to the system
bootloader or go back to the application. The file with firmware must be in binary format (.bin).
