The keyboard was not recognized by STM32H743VIT6, but was recognized by STM32F407VGT6.

[RhSilicon]

Hi,

I generated a new project in STM32CubeIDE for STM32H743VIT6, as I have already done for STM32F407VGT6 for some years.

But the keyboard was not recognized by STM32F743VIT6.

I know that STM32F743VIT6 is working because it can recognize the Mouse.

There's probably some difference in the Class codes, it's nice to get that right, as the keyboard should be the first thing anyone will try with the USB Host.

[waclawek.jan]

Debug as usually - gain deep understanding of the standards (USB, HID) and the hardware (OTG module) involved, observe behaviour, compare to expected one. It's unlikely you would be able to debug this without observing the bus (including VBUS) - a protocol analyzer is helpful, but for the initial connection issues maybe an oscilloscope or LA would suffice (some come with USB protocol decoding too).

There may be multiple issues with various keyboards, e.g. https://stcommunity.st.com/t5/embedded-software-mcus/usb-host/m-p/427675/highlight/true#M32443 . Not all keyboards are created equal, and to build hardware (e.g. proper power supply) and write software which handles many/most of them is nontrivial. Depending on your application, you may go the other route, i.e. select a keyboard which works with whatever setup you have.

JW

[RhSilicon]

I understand now, why the forum names users "Evangelist" it takes a lot of faith and persistence to make it work.