83. Structures-ii

Question.1

Two developers access a peripheral register at address 0x40010000:

Style A — Struct overlay:

typedef struct {
   volatile uint32_t CTRL;
   volatile uint32_t STATUS;
   volatile uint32_t DATA;
} Periph;
#define PERIPH ((Periph*)0x40010000)
PERIPH->CTRL = 0x01;

Style B — Direct pointer:

#define CTRL  (*(volatile uint32_t*)0x40010000)
#define STATUS (*(volatile uint32_t*)0x40010004)
CTRL = 0x01;

Which is better for a peripheral with 10+ registers?

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Style A — struct groups all registers, offsets are automatic, and adding registers is easy
Style B — direct defines are simpler and more portable
Both are equivalent in every way
Neither — registers should be accessed via function calls only