SPI data register needs option for 8-bit access about stm32f30x HOT 3 OPEN

to write a single data frame, but at that point, one may as well be using C. :)

Or you could write an extension trait implement it on the register type and then be able to write: spi.dr.write_u8(0xaa).

The proper way to fix this in the SVD file is to use overloaded registers. Basically you declare two registers at the same address in the SVD file and then svd2rust gives you an API to use the register as one variant or the other so would be able to write spi.dr8.write(0xaa) or spi.dr16.write(0xaaaa). Or least that how it should work; svd2rust doesn't currently know how to handle "overloaded registers" so it just emits API for one of the registers.

Yet another way would be to extend the register API generated by svd2rust to provide methods to directly write to the upper / lower half-word / byte. But that method would be unsafe by default as the register may have "meaning" (configuration register) instead of just being a data register. Perhaps there can be some mechanism to opt into safety; for example the bits method becomes safe when <writeConstraint> in the SVD file says that the whole range is safe to use.

from stm32f30x.

any solution to this yet? AFAIK this is still a problem and in recent rust nightlies the workaround above results in compilation failures:

error: assigning to `&T` is undefined behavior, consider using an `UnsafeCell`

from stm32f30x.

Also related: stm32-rs/stm32-rs#755

from stm32f30x.