Summary quiz

Port C of 8255 can function independently as

• input port

• output port

• either input or output ports

• both input and output ports

All the functions of the ports of 8255 are achieved by programming the bits of an internal register called

• data bus control

• read logic control

• control word register

• none of the mentioned

The device that receives or transmits data upon the execution of input or output instructions by the microprocessor is

• control word register

• read/write control logic

• 3-state bidirectional buffer

• none of the mentioned

In 8255, the port that is used for the generation of handshake lines in mode 1 or mode 2 is

• port A

• port B

• port C Lower

• port C Upper

In 8255, If A1=0, A0=1 then the input read cycle is performed from

• port A to data bus

• port B to data bus

• port C to data bus

• CWR to data bus

In the I/O mode, the 8255 ports work as

• reset pins

• set pins

• programmable I/O ports

• only output ports

In 8255, If the value of the pin STB (Strobe Input) falls to low level, then

• input port is loaded into input latches

• input port is loaded into output latches

• output port is loaded into input latches

• output port is loaded into output latches

The signals that are provided to maintain proper data flow and synchronization between the data transmitter and receiver are

• handshaking signals

• control signals

• input signals

• none

Which out of the four ports of 8051 needs a pull-up resistor for using it is as an input or an output port?

• PORT 0

• PORT 1

• PORT 2

• PORT 3

Which addressing mode is used in pushing or popping any element on or from the stack?

• immediate

• direct

• indirect

• register