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The registers that are not accessible by the user are
a) Accumulator and B register
b) IP and IE
c) Instruction registers
d) TMP1 and TMP2
…………
Answer: d
Explanation: The arithmetic operations are performed over the operands held by the temporary registers, TMP1 and TMP2. Users cannot access these temporary registers.
The register that provides control and status information about serial port is
a) IP
b) IE
c) TSCON
d) PCON and SCON
……….
Answer: d
Explanation: The registers, PCON and SCON contain control and status information about serial port.
The register that provides control and status information about counters is
a) IP
b) TMOD
c) TSCON
d) PCON
………..
Answer: b
Explanation: The registers, TMOD and TCON contain control and status information about timers/counters.
The receive buffer of serial data buffer is a
a) serial-in parallel-out register
b) parallel-in serial-out register
c) serial-in serial-out register
d) parallel-in parallel-out register
………….
Answer: a
Explanation: The serial data register has two buffers. The transmit buffer is a parallel-in serial-out register and receive buffer is a parallel-in serial-out register.
The architecture of 8051 consists of
a) 4 latches
b) 2 timer registers
c) 4 on-chip I/O ports
d) all of the mentioned
…………
Answer: d
Explanation: The architecture of 8051 consists of 4 latches and driver pairs are allotted to each of the four on-chip I/O ports. It contains two 16-bit timer registers.
The registers that contain the status information is
a) control registers
b) instruction registers
c) program status word
d) all of the mentioned
…………
Answer: c
Explanation: The set of flags of program status word contains the status information and is considered as one of the special function registers.
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