Managing an 8-bit variable instead of a 32-bit variable (Cortex-M4)

Hi everyone,

I'm trying to find an answer to my question in the previous posts, but I haven't found it.

I have an "academic" question about Cortex-M4 architecture: considering the typedef variable names in the stdint library (uint32_t, int32_t, uint8_t, etc.) in a Cortex-M4 what is the variable type to archive the fastest write/read access way?

In other words, if I use a 8-bit variable as "flag" variable, a 32-bit MCU (as Cortex-M4) needs additional operational (e.g.: hardware mask, etc.) to manage a 8-bit variable instead of a "native" 32-bit variable?

Thank you,