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Embedded Systems 2016/2017/2018: Theory [6/9 credits course]

Vfaster processor. FThe Instruction4) Set Architecture of a Single Purpose Processor is normally customizable.F5) 2 input/output ports.The Intel 8051 model used in the homelab has onlyVMemories are non-volatile ones.Phase Change6) V7) It is possible to use floating-point arithmetic also on processors without a FPU. F8) If the utilization factor of a task set is lower than 1, the task set cannot be scheduled with RM.

QUESTIONS

OPEN

1) Describe the problems related to interrupt handling mechanism in a real-time kernel and expose three possible approaches to avoid these problems.

2) Describe the different "Processors Technologies" and their main differences.

3) What are the main differences between polling-based I/O and interrupt-based I/O?

1. TRUE or FALSE? Embedded Systems are often used to introduce innovation in traditional products.
2. TRUE or FALSE? To exploit a General Purpose Processor, it is needed a compiler for a specific Instruction Set Architecture.
3. TRUE or FALSE? If the Time-To-Market of a product is 6 months, the time available to reach the market in the best moment is 6 months.
4. TRUE or FALSE? Applications Specific Instructions Processor is never customizable.
5. TRUE or FALSE? The Instruction Set Architecture of an Intel 8051 model fused in the homelab has only 2 input/output ports.
6. TRUE or FALSE? EPROM memories are non-volatile.
7. TRUE or FALSE? Arithmetic operations are also possible on processors without a FPU.
8. Given the following nesC code related to an event management...

event void myTimer.fired(){
counter++;
call Leds.Led0Toggle();
if (!busy){
BlinkToRadioMsg* btrpkt = (BlinkToRadioMsg*)(call Packet.getPayload(&pkt, NULL));
btrpkt->nodeid =

TOS_NODE_ID;
btrpkt->counter = counter;
if (call AMSend.send(AM_BROADCAST_ADDR, &pkt, sizeof(BlinkToRadioMsg)) == SUCCESS){
    busy = TRUE;
}
}}}

F ce ne sono 3it calls 4 different commands.

OPEN QUESTIONS

1) Describe the main features of fixed and vectored interrupt management techniques and highlight their differences.

2) Describe the main features of a re-entrant function and discuss at least one situation in which it is useful.

3) Describe the main features of a typical HW/SW timer implementation.

EMBEDDED SYSTEMS 2016/2017/2018: THEORY [6/9 credits course]

8 T/F questions: 0.5 points for right answers, -0.25 points for wrong ones, and 0 for no answer

3 open questions: up to 2 points for right and complete answers

Max total: 10 points

Available time: 60 minutes

Name:__________________________________________________________________________

TRUE or FALSE?

F1) An embedded system is always designed to be as general-purpose as possible.

a Single Purpose Processor, it is always needed a compiler for

the IA-32 Instruction Set

To exploit2) FArchitecture. Fis never possible to perform preemption of kernel processes.

It3) The Instruction Set Architecture of an Applications Specific Instructions Processor is normally

Vcustomizable. Vhas 4 input/output ports.

The Intel 8051 model used in the homelab5) VPhase Change Memories are volatile ones.

6) F

7) It is not possible to use floating-point arithmetic on processors without a Floating Point Unit.V

8) If the utilization factor of a task set is greater than 1, the task set cannot be scheduled.

OPEN QUESTIONS

1) What is the Design Productivity Gap?

2) With respect to 8051 Homelab: describe the differences between ISASim and a simulation based on aVHDL model.

3) Describe the main features of nesC and TinyOS.

EMBEDDED SYSTEMS 2016/2017/2018: THEORY [6/9 credits course]

8 T/F questions: 0.5 points for right answers, -0.25 points for wrong ones, and 0 for no answer

3 open questions: up to 2 points for right and complete answers

Max total: 10

pointsAvailable time: 60 minutes

Name:__________________________________________________________________________

TRUE or FALSE?

F1) A general-purpose system is always designed to be as much application-specific as possible.

2) A functionality is implemented in SW (i.e. indirectly) if described in C and executed by means of a soft-Vprocessor.

3) problem.The opportunity to perform preemption of kernel processes allows to avoid the priority inversion VThe Instruction Set Architecture of an Applications Specific Instructions Processor is customizable.

4) VThe Intel 8051 model used in the homelab has 4 input/output ports.

5) F

6) DDR RAM are non-volatile memory.

F

7) It is not possible to use integer arithmetic on processors with a FPU.

Given the following nesC code related to an event management …

8) event void myTimer.fired(){ counter++;call Leds.Led0Toggle();if (!busy){ BlinkToRadioMsg* btrpkt = (BlinkToRadioMsg*)(call Packet.getPayload(&pkt, NULL));btrpkt->nodeid =

TOS_NODE_ID;
btrpkt->counter = counter;
if (call AMSend.send(AM_BROADCAST_ADDR, &pkt, sizeof(BlinkToRadioMsg)) == SUCCESS){
    busy = TRUE;
}
}
Fit post 1 task.

OPEN QUESTIONS
1) Describe what is a split-phase operation in TinyOS.
2) Describe the possible roles of the time in an embedded system and their main differences.
3) Describe the different “Processors Technologies” and their main differences.
3) Given the following code, complete the sequence diagram (reporting comments when needed), indicating
all the possible calls and events in the 1000 ms of execution after the first indicated event.

module BlinkC()
configuration BlinkAppC {
    uses interface Timer<TMilli> as Timer0;
    uses interface Timer<TMilli> as Timer1;
    uses interface Timer<TMilli> as Timer2;
    uses interface Leds;
    uses interface Boot;
}
implementation {
    components MainC, BlinkC, LedsC;
    components new TimerMilliC() as Timer0;
    components new TimerMilliC() as Timer1;
    components new TimerMilliC() as Timer2;
}

1. TRUE or FALSE?
   1. An embedded system is always designed to be as general-purpose as possible.
   2. To exploit a General Purpose Processor, it is always needed a compiler for the IA-32 Instruction Set Architecture.
   3. The

opportunity to perform of kernel processes allows to avoid the priority inversionpreemptionproblem.

The Instruction Set Architecture of an Applications Specific Instructions Processor is normally4) Vcustomizable.

The Intel 8051 model used in the homelab has 4 input/output ports.5) V

Phase Change Memories are volatile ones.6) F

to use floating-point arithmetic on processors without a Floating Point Unit.It is not possible V

If the utilization factor of a task set is greater than 1, the task set cannot be scheduled.

OPEN QUESTIONS

1. Describe the different “Processors Technologies” and their main differences.
2. Describe the RM and EDF scheduling algorithms and their main differences.
3. Given the following code, describe the behavior of the related application and complete the sequencediagram (reporting comments, if needed), indicating all the (possible) calls and events in the first 1000 ms ofexecution (after the first indicated event). module BlinkC()configuration

BlinkAppC {{ uses interface Timer<TMilli> as Timer0;}
uses interface Timer<TMilli> as Timer1;
implementation uses interface Timer<TMilli> as Timer2;
{ uses interface Leds;
components MainC, BlinkC, LedsC;
uses interface Boot;
components new TimerMilliC() as Timer0; }
components new TimerMilliC() as Timer1;
components new TimerMilliC() as Timer2;
implementation{
event void Boot.booted()
BlinkC -> MainC.Boot;
{ call Timer0.startPeriodic( 200 );
BlinkC.Timer0 -> Timer0;
call Timer1.startPeriodic( 350 );
BlinkC.Timer1 -> Timer1;
call Timer2.startPeriodic( 950 );
BlinkC.Timer2 -> Timer2; }
BlinkC.Leds -> LedsC;}
event void Timer0.fired(){ call Leds.led0Toggle();}
event void Timer1.fired(){ call Leds.led1Toggle();}
event void Timer2.fired(){ call Leds.led2Toggle();}}

EMBEDDED SYSTEMS 2016/2017/2018: THEORY [6/9 credits course]
8 T/F questions: 0.5 points for right answers, -0.25 points for wrong ones, and 0 for no answer
3 open questions: up to 2 points for right and

Max total: 10 points

Available time: 75 minutes

Name:__________________________________________________________________________

TRUE or FALSE?

1) Vto introduce innovation in traditional products.

2) Embedded Systems are often used of a product is 6 months the time available to reach the market in the best

3) Fmoment is 6 months.

4) FThe Instruction Set Architecture of an Applications Specific Instructions Processor is never customizable.

5) FThe Intel 8051 model used in the homelab has only 2 input/output ports.

6) V2E PROM are non-volatile memory.

7) Microcontrollers are System-on-Chip that integrates a Micro Processing Unit and severalVmemories and peripherals

8) Given the following nesC code related to an event management …event void myTimer.fired(){ counter++;call Leds.Led0Toggle();if (!busy){ BlinkToRadioMsg* btrpkt =