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Microcontroller part 5
- 1. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Embedded System PART5 (Timers) ENG.KEROLES SHENOUDA 1
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- 3. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Previous session3 Covered those points Interrupt definition & Servicing Interrupts IVT & ISR & Vector Section Polling vs. Interrupt Steps in executing an interrupt Sequential interrupt processing VS Nested interrupt processing Types of Interrupts Interrupt Controller Examples On Interrupt Controllers Interrupt Controller On Atmega32
- 4. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here How togenerate assembly file from elf image (executable file)? 4
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- 6. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Add thiscommand on your MakeFile 6
- 7. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Then Buildyou will see ATMEGA32_Drivers_disassemply.txt is generated 7 Now you can see the _Vectors section
- 8. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here 8 Interrupts &Timers Interrupt Latency: Time from event to execution of service routine Interrupt Response Time: Interrupt latency + Time for service routine Interrupt Termination: Time taken after interrupt service routine
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- 10. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here What isa timer ? At a high level, a timer is just a “Counter” register that counts up or down automatically. A Counter can be used to keep track of time. It can increment/decrement a count register based on a clock and to check if the count has reached some value and trigger an action. 17 Peripherals Timers generally have a resolution of 8 or 16 or 32 Bits. So a 8 bit timer is 8Bits wide so capable of holding value within 0-255. But this register has a magical property ! Its value increases/decreases automatically at a predefined rate (supplied by user). This is the timer clock. And this operation does not need CPU’s attention. 10
- 11. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Counters Counter:like a timer, but counts pulses on a general input signal rather than clock e.g., count cars passing over a sensor Can often configure device as either a timer or counter 11 16-bit up counter Clk 16 Cnt_in 2x1 mux Mode Timer/counter Top Reset Cnt
- 12. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here HOW TOCOUNT… Up: the timer starts at zero, then counts up until it hits some maximum value. The maximum value is stored in a special register called a compare register. The maximum value can be the largest value the timer register can hold (like 0xFF for 1Byte Counter) or some arbitrary value. Down: the timer starts at some value you set and counts down until it reaches zero. Up/Down: the timer counts up until it reaches the value in the compare register, and then counts down until it reaches zero. 12 Counter register External source Oscillator Counter/Timer COUT 0 1 Flag
- 13. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer usedto … timer will produce a regular output with the same accuracy as the input clock. This output could be used to generate a periodic interrupt like a real-time operating system (RTOS) timer tick. provide a baud rate clock to a UART. drive any device that requires a regular pulse. Delay generating Counting Wave-form generating Capturing 13
- 14. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer InfraStructure 14 If we want to calculate 1ms CLK Oscillator = 24 MHz Timer clock= (24 / 12) MHz = 2 MHz Timer cycle = 500ns Delay count = delay time / cycle time 1 ms / 500 ns = 2000 Counter numbers= (216 -1)-2000 = 63535 Set Count value 63535 to max or set count 0 > 2000-1 16-bit counterClk 16 External Clock 2x1 mux Mode Controller irq Reset Cnt ÷ Clock Divider External Input Pin Output pin
- 15. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer InfraStructure Timer May have a number of counters is called Channel Each channel have a counter 15
- 16. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer ModesGroup 16 Synchronous Modes/ Cascaded counters Asynchronous Mode/ Independent Modes• The Master Channel Out will Control the other Channels • Maybe each channel/counter runs in different Mode
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- 18. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Watchdog (WDOG) WDOG is intended to be used to apply a reset to a system in the event of a failure. WDOG consists of counter with a programmable timeout interval that has the capability to generate an interrupt and a reset signal on timing out. For normal operation – the software has to ensure that the counter never reaches zero (“kicking the dog”) Usually WDOG interrupt is set with highest priority. 18
- 19. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timers inATMEGA32 TWO 8-BIT TIMERS AND ONE 16-BIT TIMER IN ATMEGA32 19
- 20. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timers inATMEGA32 TCNTn (Timer/Counter register) TOVn (Timer Overflow flag) TCCRn (Timer Counter control register) OCRn (output compare register) OCFn (output compare match flag) 20 Flag Counter register External source Oscillator Counter/Timer TCNTn TCCRn TOVn OCRn = OCFn Comment: All of the timer registers are byte-addressable I/O registers
- 21. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Atmega 32Timer 0 Modes Normal Mode Clear Timer on Compare Match (CTC) Mode Fast PWM Mode Phase Correct PWM Mode 21
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- 25. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Normal Mode The simplest mode of operation is the Normal mode (WGM01:0 = 0). In this mode the counting direction is always up (incrementing), and no counter clear is performed. The counter simply overruns when it passes its maximum 8-bit value (TOP = 0xFF) and then restarts from the bottom (0x00). In normal operation the Timer/Counter Overflow Flag (TOV0) will be set in the same timer clock cycle as the TCNT0 becomes zero. The TOV0 Flag in this case behaves like a ninth bit, except that it is only set, not cleared. However, combined with the timer overflow interrupt that automatically clears the TOV0 Flag, the timer resolution can be increased by software. There are no special cases to consider in the Normal mode, a new counter value can be written anytime. The Output Compare unit can be used to generate interrupts at some given time. Using the Output Compare to generate waveforms in Normal mode is not recommended, since this will occupy too much ofthe CPU time. 25
- 26. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here OCF2 TOV2ICF1 OCF1A OCF1B TOV1 OCF0 TOV0 TIFR TCNT0 TCCR0 TOV0 OCR0 = OCF0 Timer 0 (an 8-bit timer) 26
- 27. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here TCCR0 COM01WGM00FOC0COM00 CS02 CS01 CS00 TCCR0WGM01 CS02 CS01 CS00 Comment 0 0 0 No clock source (Timer/Counter stopped) 0 0 1 clk (No Prescaling) 0 1 0 clk / 8 0 1 1 clk / 64 1 0 0 clk / 256 1 0 1 clk / 1024 1 1 0 External clock source on T0 pin. Clock on falling edge 1 1 1 External clock source on T0 pin. Clock on rising edge Clock Selector (CS) WGM00 WGM01 Comment 0 0 Normal 0 1 CTC (Clear Timer on Compare Match) 1 0 PWM, phase correct 1 1 Fast PWM Timer Mode (WGM) 10-bit T/C Prescaler Clear 0 CS00 CS01 CS02 T0 clkIO PSR10 Timer/Counter0 clock source clk/1024 clk/256 clk/64 clk/8 0 1 2 3 4 5 6 7 27
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- 31. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here $100 ==256 -$0E $F2 14 = $0E COM01WGM00FOC0 COM00 CS02 CS01 CS00 TCCR0WGM01 0 0 10 0 Counter Register COUT UP Load 8 $F2 10-bit T/C Prescaler Clear 0 CS00 CS01 CS02 T0 clkIO PSR10 Timer/Counter0 clock source clk/1024 clk/256 clk/64 clk/8 0 1 2 3 4 5 6 7
- 32. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Example 1:write a program that waits 14 machine cycles in Normal mode. DDRB = 1<<5; PORTB &= ~(1<<5); //PB5=0 while (1) { TCNT0 = 0xF2; TCCR0 = 0x01; while((TIFR&(1<<TOV0))==0); TCCR0 = 0; PORTB = PORTB^(1<<5); } COM01WGM00FOC0 COM00 CS02 CS01 CS00 TCCR0WGM01 $100 -$0E $F2 0xFF TCNT0 0 TOV time 0xF2
- 33. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here How tocalculate the delay generated by the timer? 1) Calculate how much a machine clock = 1/f 2) Calculate how many machine clocks it waits. 3) Delay = T * number of machine cycles
- 34. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Example 1:iffrequency 10 MHZ Solution 1 (inaccurate): 1) Calculating T: T = 1/f = 1/10M = 0.1µs 2) Calculating number of machine cycles: $100 -$F2 $0E = 14 3) Calculating delay 14 * 0.1µs = 1.4 0µs
- 35. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Generating LargeDelays Using loop Prescaler Bigger counters (Counter Register width) 35 10-bit T/C Prescaler Clear 0 CS00 CS01 CS02 T0 clkIO PSR10 Timer/Counter0 clock source clk/1024 clk/256 clk/64 clk/8 0 1 2 3 4 5 6 7
- 36. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Clear Timeron Compare Match (CTC) Mode In Clear Timer on Compare or CTC mode (WGM01:0 = 2), the OCR0 Register is used to manipulate the counter resolution. In CTC mode the counter is cleared to zero when the counter value (TCNT0) matches the OCR0. The OCR0 defines the top value for the counter, hence also its resolution. This mode allows greater control of the Compare Match output frequency. It also simplifies the operation of counting external events. The timing diagram for the CTC mode is shown in the figure below. The counter value (TCNT0) increases until a Compare Match occurs between TCNT0 and OCR0, and then counter (TCNT0) is cleared. 36
- 37. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here CTC (ClearTimer on Compare match) mode TCNT0 0 OCF0OCF0 OCF0 time 0TOV0: 0 1 2 xx TOV0 = no change OCF0 = 1 OCR0 OCR0 0OCF0: 1 0xFF 37
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- 40. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Example 2:toggle led each 5 µs if you have a frequency = XTAL = 10 MHZ by Using compare match mode Because XTAL = 10 MHz, the counter counts up every 0.1 µs. This means that we need 5 µs / 0.1 µs = 50 clocks. Therefore, we have OCR0= 49. DDRB |= 1<<3; PORTB &= ~(1<<3); while (1) { OCR0 = 49; TCCR0 = 0x09; while((TIFR&(1<<OCF0))==0); TCCR0 = 0; //stop timer0 PORTB.3 = ~PORTB.3; } COM01WGM00FOC0 COM00 CS02 CS01 CS00 TCCR0WGM01 40
- 41. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer Lab1 (OVF) interrupt Write a program uses Timer0 to generate a square wave on pin PORTB.5, while at the same time data is being transferred from PORTC to PORTD. +5 PORTCPORTD 88 PORTB.5 ATmega32 41
- 42. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here ISR(TIMER0_OVF_vect) //ISR for Timer0 overflow 42
- 43. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here usingTimer0 and CTC mode generate a square wave on pin PORTB.5, while at the same time data is being transferred from PORTC to PORTD. with 100 microS Timer Lab 2 compare match interrupt Time (µS) 44 F =1 MHZ 100*10^-6 / 10^-6 = Counter Numbers = 100 Compare Match = 100 – 1 =99 (start from 0 to 99)
- 44. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer2 Timer0 Timer2 OCF2 TOV2 ICF1 OCF1A OCF1B TOV1 OCF0 TOV0 TIFR TCNT2 TCCR2 TOV2 OCR2 = OCF2 TCNT0 TCCR0 TOV0 OCR0 = OCF0 46
- 45. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here The differencebetween Timer0 and Timer2 Timer0 Timer2 CS02 CS01 CS00 Comment 0 0 0 Timer/Counter stopped 0 0 1 clk (No Prescaling) 0 1 0 clk / 8 0 1 1 clk / 64 1 0 0 clk / 256 1 0 1 clk / 1024 1 1 0 External clock (falling edge) 1 1 1 External clock (rising edge) CS22 CS21 CS20 Comment 0 0 0 Timer/Counter stopped 0 0 1 clk (No Prescaling) 0 1 0 clk / 8 0 1 1 clk / 32 1 0 0 clk / 64 1 0 1 clk / 128 1 1 0 clk / 256 1 1 1 clk / 1024 47
- 46. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer 1 OCF2TOV2 ICF1 OCF1A OCF1B TOV1 OCF0 TOV0 TIFR TCNT1H TCNT1LTCCR1B TOV1 OCR1AH OCR1AL = OCF1A = OCF1B OCR1BH OCR1BL TCCR1A 48
- 47. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer 1 WGM13CS12 CS11 CS10WGM12ICNC1 ICES1 - TCCR1B CS12 CS11 CS10 Comment 0 0 0 No clock source (Timer/Counter stopped) 0 0 1 clk (No Prescaling) 0 1 0 clk / 8 0 1 1 clk / 64 1 0 0 clk / 256 1 0 1 clk / 1024 1 1 0 External clock source on T0 pin. Clock on falling edge 1 1 1 External clock source on T0 pin. Clock on rising edge Clock Selector (CS) COM1B1 WGM11FOC1BCOM1B0 WGM10FOC1ACOM1A0COM1A1 TCCR1A 10-bit T/C Prescaler Clear 0 CS10 CS11 CS12 T1 clkIO PSR10 Timer/Counter1 clock source clk/1024 clk/256 clk/64 clk/8 0 1 2 3 4 5 6 7 49
- 48. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer 1WGM13 CS12 CS11 CS10WGM12ICNC1 ICES1 - TCCR1B COM1B1 WGM11FOC1BCOM1B0 WGM10FOC1ACOM1A0COM1A1 TCCR1A 50
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- 50. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here What isPWM ? A PWM Signal is a periodic rectangular pulse. Frequency = 1/T Duty Cycle = (T_ON/T) Pulse width modulation (PWM) is a powerful technique for controlling analog circuits with a microprocessor's digital outputs. PWM is employed in a wide variety of applications, ranging from measurement and communications to power control and conversion. 52
- 51. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here What isneed of PWM? PWM is mainly used for controlling the speed of DC motors . By pulse width modulation we can get a variable voltage digitally, that is we get voltages between 0 and VCC by switching the VCC on and off periodically . Other applications are fading Led , getting different tones in Buzzer,Contolling the degree of rotation of Servo motor . 53
- 52. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here How DoesA Servo Motor Work? Usually a servomotor turns 90° in either direction, i.e. maximum movement can be 180° Three wires are taken out of a servo: positive, ground and control wire. A servo motor is controlled by sending a Pulse Width Modulated (PWM) signal through the control wire. A pulse is sent every 20 milliseconds. Width of the pulses determine the position of the shaft. For example, a pulse of 1ms will move the shaft anticlockwise at -90°, a pulse of 1.5ms will move the shaft at the neutral position that 0° and a pulse of 2ms will move the shaft clockwise at +90 54
- 53. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here How DoesA Servo Motor Work? Width of the pulses determine the position of the shaft. For example, a pulse of 1ms will move the shaft anticlockwise at -90°, a pulse of 1.5ms will move the shaft at the neutral position that 0° and a pulse of 2ms will move the shaft clockwise at +90 55
- 54. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Servo motor Servo motor works on PWM (Pulse width modulation) principle, means its angle of rotation is controlled by the duration of applied pulse to its Control PIN. Basically servo motor is made up of DC motor which is controlled by a variable resistor (potentiometer) and some gears 56
- 55. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Servo motor(another degree range)(Motor-PWMSERVO in ISIS) Servo motor can be rotated from 0 to 180 degree, but it can go up to 210 degree, depending on the manufacturing. This degree of rotation can be controlled by applying the Electrical Pulse of proper width, to its Control pin. Servo checks the pulse in every 20 milliseconds. Pulse of 1 ms (1 millisecond) width can rotate servo to 0 degree, 1.5ms can rotate to 90 degree (neutral position) and 2 ms pulse can rotate it to 180 degree. 57
- 56. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Lab1/Test ServoMotor By Atmega 32 With out any timer, run a servo Motor (Motor-PWMSERVO ) in ISIS Angle 0,90 and 180 as shown below 58
- 57. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Lab1/Test ServoMotor By Atmega 32 With out any timer, run a servo Motor (Motor-PWMSERVO ) in ISIS Angle 0,90 and 180 as shown below 59
- 58. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Lab1/Test ServoMotor By Atmega 32 With out any timer, run a servo Motor (Motor-PWMSERVO ) in ISIS Angle 0,90 and 180 as shown below 60
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- 60. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here DC Motor This DC or direct current motor works on the principal, when a current carrying conductor is placed in a magnetic field, it experiences a torque and has a tendency to move. 62
- 61. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Lab2/ writeembedded C Code without timer to run two DC Motors First DC Motor Connect to PD0 (run Clockwise) Second DC Motor Connect to PD1 (run Anticlockwise) Sequence (Motor 1 run) > Motor1 stop & Motor 2 run And so on Choose the time you prefer 63
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- 64. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here We can’tconnect a DC Motor directly to a microcontroller ? A microcontroller can’t supply the current required for the working of DC Motor. ATmega32 Microcontroller can source or sink currents up to 40mA but a DC Motor needs current very much more than that. The negative voltages created due to the back emf of the motor may affect the proper functioning of the microcontroller. You may need to control the direction of rotation of the motor by changing the polarity of the motor supply. The operating voltage of the DC Motor may be much higher than the operating voltage of the microcontroller. 66
- 65. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here L293D Tosolve these problems you may use transistorized H Bridge in which freewheeling diodes are used to avoid problems due to back emf. Thus it requires minimum four transistors, diodes and resistors for each motor. It is better to use readymade ICs such as L293D or L293instead of making your own H Bridge, which simplifies your project. L293D is a Quadruple Half H-Bridge driver commonly used for motor driving. We needn’t connect any transistors, resistors or freewheeling diodes. All the four outputs of this IC are TTL compatible and output clamp diodes are provided to drive inductive loads. L293D can provide up to 600mA current, in the voltage raging from 4.5 to 36v. L293 is a similar IC which can provide up to 1A in the same voltage range. L293 or L293D contains four Half H Bridge drivers and are enabled in pairs. Input EN1 is used to enable pair 1 (IN1-OUT1, IN2-OUT2) and input EN2 is used to enable pair 2 (IN3-OUT3, IN4-OUT4). We can drive two DC Motors with one L293D, but here for demonstration we are using only one. You can connect second DC Motor to driver pair 2 according to your needs. 67
- 66. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Control Signalsand Motor Status PC0/IN1 PC1/IN2 Motor Status LOW LOW Stops LOW HIGH Clockwise HIGH LOW Anti-Clockwise HIGH HIGH Stops 68
- 67. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here If wecan generate PWM by GPIO and Delay, Why we need to use TIMER Module to generate PWM ? 69
- 68. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Atmega 32Timer 0 Modes Normal Mode Clear Timer on Compare Match (CTC) Mode Fast PWM Mode Phase Correct PWM Mode 70
- 69. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Hand WritingNotes: we took it on the previous Lecture 71
- 70. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Request timeequation 72 Some Times We need t used SW Counters (looping) Increment SW Counter after each Timer ISR That make us to increase the Required delay range
- 71. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Normal Mode The simplest mode of operation is the Normal mode (WGM01:0 = 0). In this mode the counting direction is always up (incrementing), and no counter clear is performed. The counter simply overruns when it passes its maximum 8-bit value (TOP = 0xFF) and then restarts from the bottom (0x00). In normal operation the Timer/Counter Overflow Flag (TOV0) will be set in the same timer clock cycle as the TCNT0 becomes zero. The TOV0 Flag in this case behaves like a ninth bit, except that it is only set, not cleared. However, combined with the timer overflow interrupt that automatically clears the TOV0 Flag, the timer resolution can be increased by software. There are no special cases to consider in the Normal mode, a new counter value can be written anytime. The Output Compare unit can be used to generate interrupts at some given time. Using the Output Compare to generate waveforms in Normal mode is not recommended, since this will occupy too much ofthe CPU time. 73
- 72. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Clear Timeron Compare Match (CTC) Mode In Clear Timer on Compare or CTC mode (WGM01:0 = 2), the OCR0 Register is used to manipulate the counter resolution. In CTC mode the counter is cleared to zero when the counter value (TCNT0) matches the OCR0. The OCR0 defines the top value for the counter, hence also its resolution. This mode allows greater control of the Compare Match output frequency. It also simplifies the operation of counting external events. The timing diagram for the CTC mode is shown in the figure below. The counter value (TCNT0) increases until a Compare Match occurs between TCNT0 and OCR0, and then counter (TCNT0) is cleared. 74
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- 74. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Phase CorrectPWM Mode, Timing Diagram 76
- 75. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Timer/Counter TimingDiagrams No prescaling With prescaling 77
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- 86. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here How towrite Driver for Timer0 88
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- 96. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Assignment 1 Repeat the Servo/DC Motor Labs by Using the Timer 98
- 97. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here Assignment 2 Complete the Timer0 Driver to Support the other Modes. 99
- 98. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here References http://techdifferences.com/difference-between-interrupt-and-polling-in- os.html http://www.bogotobogo.com/Embedded/hardware_interrupt_software_inter rupt_latency_irq_vs_fiq.php Preventing Interrupt Overload Presented by Jiyong Park Seoul National University, Korea 2005. 2. 22. John Regehr, Usit Duogsaa, School of Computing, University. First Steps Embedded Systems Byte Craft Limited reference COMPUTER ORGANIZATION AND ARCHITECTURE DESIGNING FOR PERFORMANCE EIGHTH EDITION William Stallings Getting Started with the Tiva™ TM4C123G LaunchPad Workshop 100
- 99. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here References Tiva™TM4C123GH6PM Microcontroller DATA SHEET Interrupts and Exceptions COMS W6998 Spring 2010 THE AVR MICROCONTROLLER. AND EMBEDDED SYSTEMS Using Assembly and C. Muhammad Ali Mazidi. 101
- 100. https://www.facebook.com/groups/embedded.system.KS/ Follow us Press here References https://docs.google.com/viewer?a=v&pid=sites&srcid=ZmtlLnV0bS5teXxyaWR6dW FuLXMtd2Vic2l0ZXxneDo2ODU0NzlkM2JkOTg4MjRk http://www.avrprojects.net/index.php/avr-projects/sensors/38-humidity-and- temperature-sensor-dht11?showall=&start=1 http://www.cse.wustl.edu/~lu/cse467s/slides/dsp.pdf http://www.avr-tutorials.com/ Microprocessor: ATmega32 (SEE3223-10) http://ridzuan.fke.utm.my/microprocessor-atmega32-see3223-10 http://circuitdigest.com/article/what-is-the-difference-between-microprocessor- and-microcontroller AVR Microcontroller and Embedded Systems: Using Assembly and C (Pearson Custom Electronics Technology) 1st Edition https://www.amazon.com/AVR-Microcontroller-Embedded-Systems- Electronics/dp/0138003319 102
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