超星 - 第四章作业2-单片机的中断系统 - 查题吧

单选题

When the serial port of MCS-51 MCU receives or transmits a frame of data, the () in scon is applied to CPU for interrupt.

A. RI or ti set to 1
B. RI or ti set to 0
C. RI set to 1 or ti set to 0
D. RI set to 0 or ti set to 1

单选题

When the it1 and it0 bits in the timer control register TCON are cleared to 0, the external interrupt request signal mode is ().

A. Low level active
B. High level active
C. Pulse up bound valid
D. Pulse negative jump valid

判断题

Start the timer and start it with SETB TRi.

A. 对
B. 错

判断题

The interrupt response of. 8051 MCU to the highest priority is unconditional.

A. 对
B. 错

判断题

During interrupt initialization, only bit operation instruction can be used to set the state of interrupt controller, not byte operation instruction.

A. 对
B. 错

判断题

After the MCS-51 system is reset, the interrupt request flag TCON and scon are all 0.

A. 对
B. 错

判断题

The function of IE in interrupt permission register of MCS-51 single chip microcomputer is to open or shield the interrupt sources.答案:

A. 对
B. 错

判断题

When writing interrupt service program, the user can store an unconditional transfer instruction in the interrupt entry vector address to prevent the interrupt service program from being unable to accommodate.

A. 对
B. 错

判断题

If you want to disable higher priority interrupts when executing the current interrupt program, the application software will turn off CPU interrupts, or shield interrupts from higher level interrupt sources, and then turn on interrupts when interrupts return.

A. 对
B. 错

判断题

After the CPU responds to the interrupt, it must clear the corresponding interrupt flag bit with software in the interrupt service program to cancel the interrupt request.

A. 对
B. 错

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