MTE 325 EXAM QUESTIONS AND
ANSWERS
What does a device driver include (4) - Answer- 1. data structures
2. initialization functions
3. I/O functions
4. ISRs
Active vs Passive Synchronization - Answer- Active: one of the entities is capable of
forcing a change in operational characteristics of the other
Passive: One of the communicating entities signals a request for service, however, the
entity receiving the request is not forced to respond
Global initialization - Answer- set up processor and I/O interface parameters for overall
system operation
Transfer initialization - Answer- set up processor and I/O interface parameters to
facilitate a specific type of transfer
System Bus - Answer- connects components that need to communicate w/ each other
(wires shared by several components)
ROM - Answer- Read Only Memory: contains instructions to get processor in start up
state
RAM - Answer- Random Access Memory: stores values and programs that may change
Pro and Con of synchronous systems - Answer- + : less complex signalling (less wires)
- : always have to set the speed so that the slowest device can complete transaction on
one bus clock
Interfaces - Answer- connects computer to the outside world, converts signals to
appropriate levels and timing to permit interaction w/ processor
Embedded System - Answer- a special purpose computer system designed to perform
a task w/o the user's knowledge of its existence
, Simple Embedded System vs Complex Embedded System - Answer- simple: does not
need processor and software, however there will be state (memory)
complex: have 1 or more processor w/ sophisticated control software
Hardware/Software Codesign - Answer- Simultaneously designing hardware and
software in hardware/software system
Microprocessor - Answer- Consists of a processor only (no main memory, built in i/o
support)
Microcontroller - Answer- a complete computer on a single chip consisting of a
processor, memory and some i/o devices
System-on-a-chip - Answer- (SoC) - a user-designed fully functional system
implemented on a single chip
System-on-a-programmable-chip - Answer- (SoPC) - an SoC that is implemented using
a high density reconfigurable programmable logic device (PLD)
Volatile - Answer- A keyword that tells the processor not to make optimizations to the
corresponding variable
Synchronization mechanisms (5) + describe them - Answer- 1. Occasional Polling: poll
at the connivence of the designer
2. Periodic Polling: Poll at set intervals
3. Tight Polling: Continuously poll, software does nothing other than poll
4. Blind Cycle: software waits for some amt of time then acts on data whether device is
ready or not
5. Interrupt handling: Device generates a HW interrupt to request service immediately
Polling loop synchronizations: Optimistic vs conservative option - Answer- Optimistic:
Assume device is initially ready, output data, poll device
Conservative: Assume device is not initally ready, poll the device, wait until device is
ready, output data
Non-vectored vs vectored interrupts - Answer- Non-vectored: devices are polled to
determine source
Vectored: Requests are associated w/ an interrupt handler
Process of ISR - Answer- 1. save registers
2. acknowledge device (optional)
3. re-enable interrupts
4. test for valid interrupt / determine source of interrupt
5. complete desired interrupt action
6. restore registers
7. return from interrupt
ANSWERS
What does a device driver include (4) - Answer- 1. data structures
2. initialization functions
3. I/O functions
4. ISRs
Active vs Passive Synchronization - Answer- Active: one of the entities is capable of
forcing a change in operational characteristics of the other
Passive: One of the communicating entities signals a request for service, however, the
entity receiving the request is not forced to respond
Global initialization - Answer- set up processor and I/O interface parameters for overall
system operation
Transfer initialization - Answer- set up processor and I/O interface parameters to
facilitate a specific type of transfer
System Bus - Answer- connects components that need to communicate w/ each other
(wires shared by several components)
ROM - Answer- Read Only Memory: contains instructions to get processor in start up
state
RAM - Answer- Random Access Memory: stores values and programs that may change
Pro and Con of synchronous systems - Answer- + : less complex signalling (less wires)
- : always have to set the speed so that the slowest device can complete transaction on
one bus clock
Interfaces - Answer- connects computer to the outside world, converts signals to
appropriate levels and timing to permit interaction w/ processor
Embedded System - Answer- a special purpose computer system designed to perform
a task w/o the user's knowledge of its existence
, Simple Embedded System vs Complex Embedded System - Answer- simple: does not
need processor and software, however there will be state (memory)
complex: have 1 or more processor w/ sophisticated control software
Hardware/Software Codesign - Answer- Simultaneously designing hardware and
software in hardware/software system
Microprocessor - Answer- Consists of a processor only (no main memory, built in i/o
support)
Microcontroller - Answer- a complete computer on a single chip consisting of a
processor, memory and some i/o devices
System-on-a-chip - Answer- (SoC) - a user-designed fully functional system
implemented on a single chip
System-on-a-programmable-chip - Answer- (SoPC) - an SoC that is implemented using
a high density reconfigurable programmable logic device (PLD)
Volatile - Answer- A keyword that tells the processor not to make optimizations to the
corresponding variable
Synchronization mechanisms (5) + describe them - Answer- 1. Occasional Polling: poll
at the connivence of the designer
2. Periodic Polling: Poll at set intervals
3. Tight Polling: Continuously poll, software does nothing other than poll
4. Blind Cycle: software waits for some amt of time then acts on data whether device is
ready or not
5. Interrupt handling: Device generates a HW interrupt to request service immediately
Polling loop synchronizations: Optimistic vs conservative option - Answer- Optimistic:
Assume device is initially ready, output data, poll device
Conservative: Assume device is not initally ready, poll the device, wait until device is
ready, output data
Non-vectored vs vectored interrupts - Answer- Non-vectored: devices are polled to
determine source
Vectored: Requests are associated w/ an interrupt handler
Process of ISR - Answer- 1. save registers
2. acknowledge device (optional)
3. re-enable interrupts
4. test for valid interrupt / determine source of interrupt
5. complete desired interrupt action
6. restore registers
7. return from interrupt
