[amp_mcq option1=”D” option2=”X” option3=”IPR” option4=”DI” correct=”option3″]
The correct answer is C. IPR.
The IPR (Interrupt Priority Register) is a concatenated register of the MC68HC11. It is a 4-bit register that stores the priority of the currently executing interrupt. The IPR is used to determine which interrupt will be serviced next.
The D register is a 16-bit register that is used to store data. The X register is a 16-bit register that is used to store addresses. The DI register is a 16-bit register that is used to store data and addresses.
The IPR is a more important register than the D, X, and DI registers because it determines which interrupt will be serviced next. The D, X, and DI registers are used to store data and addresses, but they do not affect the order in which interrupts are serviced.