Access to HW

Embedded systems always need to handle I/O accessed via peripheral devices.

Access to hardware is allowed for all INtime binaries. Unlike with Windows programs, no device driver programming with respective hustle for debugging is required in INtime.

At the physical level, peripheral devices either can be accessed in memory or in the I/O space of the processor.

While access in I/O space is done using respective processor instructions, memory mapped access first requires mapping of the physical memory where the peripheral device is located into the thread’s virtual memory.