Possible meaning:
The Read-Modify-Write problem Abstract: If you perform an rmw (read modify write) operation on a port register (PORTA PORTB etc) [ed: or some timer / counter registers] then you are heading for trouble. Why? Because when the uP reads a port register, it reads the actual state of the pins, rather than the output latch. ...
Other meanings:
Regulated Medical Waste
Radioactive Mixed Waste
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