Chapter 1

What was the first widely used microprocessor? In what year was it introduced and by what company?

• The 8080 by Intel in 1971

• The 8051 by Intel in 1971

• The 6502 by MOS in 1974

• The Z80 by Zilog in 1972

Two of the smaller microprocessor companies in the 1970s were MOS Technology and Zilog. Name the microprocessor that each of these companies introduced.

• MOS = 6505

  Zilog = Z70

• MOS = 6080

  Zilog = Z60

• MOS = 6502

  Zilog = Z80

What year was the 8051 microcontroller introduced? What was the predecessor to the 8051, and in what year was it introduced?

• 8051 = 1980

  8658 = 1976

• 8051 = 1980

  8748 = 1976

• 8051 = 1979

  8748 = 1976

• 8051 = 1982

  8778 = 1975

Name two types of semiconductor memory discussed in chapter 1. Which type retains its contents when powered-off? what is the common term that describes this property?

• RAM and ROM

  ROM Retains contents when powered off

  Known as nonvolatile

• RAM and ROM

  RAM Retains contents when powered off

  Known as nonvolatile

• ROM and EPROM

  EPROM Retains contents when powered off

  Known as nonvolatile

• ROM and PROM

  ROM Retains contents when powered off

  Known as Volatile

Which register in a CPU always contains an address? What address is contained in this register?

• DPTR

  Always points to next memory address

• ACC

  Always retains data for next operation

• SP

  Always holds stack instructions

• PC

  Always holds next memory address

During an opcode fetch, what is the information on the address and data buses? What is the direction of the information flow on these busses during an opcode fetch?

• Address Bus:

  Contents of PC

  Flows from RAM to CPU

  Data Bus:

  Opcode data

  Flows from CPU to RAM

• Address Bus:

  Contents of PC

  Flows from CPU to RAM

  Data Bus:

  Opcode data

  Flows from RAM to CPU

• Address Bus:

  Opcode data

  Flows from CPU to RAM

  Data Bus:

  Contents of PC

  Flows from RAM to CPU

• Address Bus:

  Opcode data

  Flows from RAM to CPU

  Data Bus:

  Contents of PC

  Flows from CPU to RAM

How many bytes of data can be address by a computer system with an 18-bit address bus and an 8-bit data bus?

• 64k

• 128k

• 256k

• 512k

Answer explanation

2^18 = 2^10 * 2^8

2^10 is approximately 1000

= 1000 * 256 = 256k

Of the three levels of software presented in chapter 1, which is the lowest level? What is the purpose of this level of software?

• Subroutines

  This directly controls the hardware

• Application software

  This directly controls the hardware

• Operating system

  This directly controls the hardware

What is the difference between an actuator and a sensor? what is an example of each?

• Actuator: Output

  Ex.) Light

  Sensor: Input

  Ex.) Speaker

• Actuator: Input

  Ex.) Switch

  Sensor: Output

  Ex.) Thermistor

• Actuator: Input

  Ex.) Phototransistor

  Sensor: Output

  Ex.) Motor

• Actuator: Output

  Ex.) Motor

  Sensor: Input

  Ex.) Phototransistor

What is firmware? Comparing a microcontroller-based system to a microprocessor-based system which is more likely to rely on firmware? Why?

• Control program stored permanently in the ROM

  Microprocessor-based system relies heavily on firmware

  Large control program stored in ROM (small RAM)

• Control program stored permanently in the RAM

  Microprocessor-based system relies heavily on firmware

  Large control program stored in RAM (small ROM)

• Control program stored permanently in the ROM

  Microcontroller-based system relies heavily on firmware

  Large control program stored in ROM (small RAM)

• Control program stored permanently in the RAM

  Microcontroller-based system relies heavily on firmware

  Large control program stored in RAM (small ROM)