IE1206. embedded Electronics. Presentations from year 2013-2014 - - PDF document

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• IE1206. embedded Electronics.

Presentations from year 2013-2014

This is a saved copy of a previous edition of the course from year 2013-2014.

Content

Exercises with Structure charts. Ex_structure_en.pdf Sequence, selection and iteration - structurediagram.

• 1. Year, ringsignals, communication means, chain.
• 2. Structur diagram - components, signals, trainset, school schedule, panel discussion.
• 3. push-ups, cake.

Introduction - mini report. F_intro_en.pdf embedded systems, development team. Simple development system!. Technical report. Assembly Image, Block diagram, Chart types for program code. Structure diagram, State chart, (flow chart). Publishing software code. fixed width font - Courier New Comments, ASCII-graphics Prototyping, Functional prototype - Product breadboard, Breakoutboard, stripboard, PCB (Electronic Cad) (Mockup) PIC-processor. F_PIC_en.pdf PIC 8-bit processor. 63 different types of Midrange PIC processors! Cheapest PIC-processor less than one dollar. IO devices increases 8-bit processors' performance Program memory (pages), Data memory - register File (Bank) SFR/GPR. PC, IR, ALU, W-register. 2-stage Pipeline. Instruktion Fetch - Execute 8 clock cykles.

• Instructionsformat. Byte operations, program constants, bit operations, jump,

Conditional tests, skip. Exeqution time. 4 MHz - 1 us (jump 2us). Ports, port pin. Tris-registers. An Assembly program. C-code. Compilation report. (Cc5x internal variables). (Cc5x internal funktions). ( Simple C- statements to Assembler ). Typical program structures.

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Initiate then eternal loop. Single run program - avoid sleep (the power saving mode) closes IO-units. Wait for a key press. Blocking code, Contact bounces, delay()-function. C-functions. TMR0. Keypresses non blocking code. Checkbox or Radiobutton? C:s Switch Case expression. Programing with state chart. Warning for the RMW-problem! Serial communication vith PIC-processor. F_PIC_COM_en.pdf ASCII-table. \r\n for return. parallell-serial-parallell conversion, UART/USART/EUSART. Bitrate. Baude rate generator. Transmitter, TXREG-TXIF. Reciever, RCREG-RCIF. Unlocking procedure.. Seriecom - Hardware. Console program. Test program echo()/crypto()

• Bitbanging. Functions rl() och rr(). getchar() putchar().

Test program 'U' - squarewave. Handling of text strings and numbers. Le_strings_en.pdf PIC-processor - computed goto C-program skip() computed goto. #pragma return[]. Strings with pointers. String start addressas function parameters. Constant and variable strings. Enter a string. Compare strings. printf()-lookalike. From binary to ASCII-string. Digital pulse sensors. Le_dig_pot_en.pdf Digital pulse sensors. Mechanical sensing, Optical sensing. State diagram. (Digital interpolation). (Reference pulse). Program example - count pulses. - missed pulses? Interrupt Lokal enable, peripherial enable, global enable. Interrupt flags. Interrupt routine #pragma origin, int_save_registers, int_restore_registers. Context saving - important!

• Examplel. RPG-interrupt program.

Computer mouse - Douglas C Engelbart Magnet sensor, Hall effectn Hall switch unipolar/bipolar Electricity.

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Le_electricity_en.pdf School model of the Magnesium atom. Periodic system. Leader/Insulator/Semiconductor. Voltage Current Resistance. Fluid analogy to DC circuits. OHM's law, current direction, conductivity. (Resistors colorcode). Conductor resistance, resistivity. Ex 2.1 - how long is the cable? Example - Voltage drop in a cable. Example - strain gauge. Resistance temperature dependence.

• Ex. What temperature has the motor winding?

Temperature ITS-90. Resistance thermometers. Four wire measurement. Ex 2.4 Three wire connection. Measure with AD-converter. PTC thermistors - Overfill protection. SI-PTC-termistor - pyramid resistance. NTC-thermistor. Electric power. U I R P. Exempel rated power.

• Ex. hotplate.
• CDS. photo potentiometer.

Triangulating. Serial and parallell circuits.. F_SerialParallel.pdf Series connected and parallell connected resistors. Series connection - equivalent resistance Parallel connection - equivalent resistance Two paral connected resistors. Parallel circuit. current branching.

• Example. not a parallel circuit - pumps.

Series circuit. Voltage division formula. Voltage divider with a load Example - voltage divider for lamps Current branching formula. Linearization of NTC thermistor. Example strain gauge. Wheatstone bridge - branched river. OHM’s law are often enough! Series-, parallel and mixed circuits ... Ex_SerParMixed_en.pdf Closed circuit? Equivalent resistance - series circuit.

• Ex. 1.2 Equivalent resistance.
• Ex. 1.6 Equivalent resistance.
• Ex. 1.1 Equivalent resistance.

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• Ex. 1.8 Equivalent resistance.
• Ex. 1.10 Potentiometer. Equivalent resistance.

(Ex. 1.11 Potentiometer vith load - voltage divider).

• Ex. 3.1 Series circuit.
• Ex. 3.4 Series - parallel circuit
• Ex. 3.3 Series - parallel circuit
• Ex. 3.5 Series - parallel circuit

Batteries Le_batteries_en.pdf The electrochemical cell function. Discharge curve and capacity.

• Ex. 4.1 capacity calculations.

Different discharge cases. Discharge current, Intermittent, temperature. Cell or Battery. Comparisons between battery types. Emf internal resistance and terminal voltage. Discharge, Charge. Series connection of cells. Example - How many cells are needed?

• Ex. 4.2 Calculate the internal resistance .

The risk with series connection - reverse cell voltage. Parallel connection of cells Electric Vehicle Battery Kirchhoffs laws. Node analysis. Le_Kirchhoff_en.pdf Kirchhoffs laws. Kirchhoff currentlaw, Kirchhoff voltage law. Work flow. OHM's law on matrix form. Webb-based tools for solving systems of equations.. Potential What is ground?

• Nodanalysis. Same exemple.

( Mesh analysis. Samea example ). Which method is most important to know and use? Equation system with Mathematica Wolfram Alpha online Simulation with LTSpice Everyone of you has got an unique web-task to solve! Voltage divider, Kirchhoffs laws, node analysis. Ex_kirchhoff_en.pdf

• Ex. Unbalanced Wheatstone bridge.
• Ex. 7.1 Potential.
• Ex. 5.3 Kirchhoff voltage law.
• Ex. 5.1 Kirchhoff current law.
• Ex. 5.2 Kirchhoff current law.
• Ex. 6.3 Kirchoff laws - ideal voltage source.

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• Ex. 7.3 (6.3) Node analysis.
• Ex. 4.4 Parallel connected batteries.

Two-terminal theorem. Superposition. Le_blackbox_en.pdf Two-terminal theorem, equivalent circuits. Voltage source or current source? Emf/Current generator. Thévenin voltage source model and Norton current source model. Open circuit voltage. Short cut current. Exchange of model. Experimental measurement of parameters.

• Ex. 8.3 Equivalent circuit.
• Ex. Equivalent circuit as a trick to simpify calculations.

Superposition. Same example as before - now with superposition.

• Ex. 8.7 Superposition.

AD-conversion. Le_ADconversion_en.pdf Digital or Analog Digital - Analog converter, sum binary coded currents. Problems with tolerances. R2R-method. R2R ladder. Constant internal resistance. Superposition of binary coded voltages. R2R simulation. AD-converter, succesive approximations. PIC-processor 14-AD-channels Supply voltage as reference. External reference. Ratiometric connection. 10 bitar left adjusted or right adjusted value. Sample & Hold. tacq Acquisition time AD-converter clock frequency. AD-conversion "step by step" AD-laboration. Le_ADlab_en.pdf Circuit elements in graphical form Two-terminal circuit with emf and resistance Define the current in the opposite direction. (Current source and resistance) Measurements at AD-lab. Circuit and equivalent. Rail splitter virtual ground chip. Measuring a bipolar voltage AD with external reference. Log measurement values to a text file

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Measured values to Excel (or online scatter plot) Simulate, parametrisc sweep. Tvo-terminal equivalents. Ex_blackbox_en.pdf Tvo-terminal circuit - blackbox The power supply. Constant voltage - constant current (current limit).

• Ex. 8.1 Voltage and Current generator .
• Ex. 8.2 Simplify current sources.
• Ex. 8.4 Equvalents step by step.

(Wheatstone bridge equivalent) Equivalent circuits (instead of mesh analysis)!.

• Ex. 7.2 current generator at node analysis.
• Ex. 8.9 equivalent circuit.
• Ex. 8.10 equivalent circuit.
• Ex. 8.11 equivalent circuit.

Capacitor, transients RC. Le_capacitance_en.pdf Plate capacitor. Dielectric. Dielectric. Area, distance. Electrolytic capacitor.

• Ex. 9.2 Supercap - rough estimate.

Capacitor transients. Timeconstant RC.

• Ex. 9.3 Parallel connected capacitors.
• Ex. 9.4 Series connected capacitors.

Energy in capacitor.

• Ex. 9.1 Camera Flash.
• Ex. 10.9 Neon lamp (Blink-circuit with Neon-lamp at exercise).

Simulate Neon lamp. Exponential progress. Le_exponential_en.pdf Rule of thumb for one timeconstant and for five.

• Ex. Quick estimate of the time constant

Quick Formula for exponential "All" by "the rest" - KTH-forula.

• Ex. measurement of the time constant

Comparator, Schmitt-trigger, 555-circuit. Le_SchmittTrigger_en.pdf Comparator an 1 bit AD-converter PIC-processor comparators - Many configuration options!. ANSEL, ANSELH, CM1CON0, CM2CON0, CM1CON1, CM1CON1 CM2 at lab.

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Schmitt-trigger.

• Ex. 10.10 Schmitt-triggern Threshold voltages.

RC-oscillator. Simulate the RC-oscillatorn. 555 as RC-oscillator. PIC-processor SR-latch. PIC-processor as 555-oscillator. Touch-control, Vandal proof button at the pedestrian crossing! Touch-control keyboard.

• Transients. RC-oscillator (Schmitt-trigger).

Ex_transient_en.pdf Continuity requirements.

• Ex. 10.5 Capacitator charging.
• Ex. 10.9 Neon lamp
• Ex. 10.10 Schmitt-trigger. RC-oscillator.
• Ex. 10.8 Inductor connection and disconnection.

Magnetism, inductance, and transients R/L. Le_inductance_en.pdf Magnetism. Permanent magnets. Flux and flux density. Field images between poles.

• Ex. 9.5 Permanent magnets.
• Permability. Relative permability.
• Ex. 9.6 Permability.

Electro magnetism. Right hand rule.

• Ex. 9.8 Magnetfield around a loop. Electromagnet. Iron core.

Motor principle. DC-motorn. Generatorprincipen. Induktion law. Lenz law.

• Ex. 9.9 Lenz law.

Inductance Induction law. Self induction. Inductance calculation. (Ex. 9.11 Half inductance?) Inductor transients. Inductor time constant L/R. Energy stored in magnetic field. Energy in capacitor and inductor. Continuity requirements. Step-up converter. Le_StepUp_en.pdf

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Energy transfer with a resistor. Energy transfer with an inductor - This in theory is completely without losses! Step Up upptransforming voltage. The coil current inertia! Voltage ratio and Dutycycle. Resistiv load - capacitor. Simulation of Step Up converter. CCP-unit, PWM. Le_PWM_en.pdf DA-conversion, usually PWM. PWM with TMR0? CCP-unit. PWM with CCP-unit. CCPR1L Dutucycle. PR2 PWM-frequency. DC1B1 and DC1B0 extra dutycycle-bits. PWM are used to Step Up and Step Down, and for motor control.

• complex_en.pdf

AC circuits. Phasor. complex method. Le_phasor_rcl_en.pdf Easy to generate a sinusoidal voltage. Parameters.

• Ex. 11.1 Sine wave with phase angle.

Mixed radians [rad] and degrees [deg]. Mean and effective value. Ex. effective value.

• Ex. 11.2 effective value.

Sine wave effective value. Sine wave as a pointer. Addition of sinusoidal quantities simpler with pointers (vectors). Ex. vector addition. Phasor with complex numbers. peak/effective value - phasor? The inductor and capacitor counteracts changes. Alternating current through resistor. Alternating current through inductor, reactance Alternating current through capacitor. Reactance has negative sign. L + C in series. Reactance frequency dependency. LIN-LIN and LOG-LOG. Impedance R L C.

• Ex. 11.5 Phasor diagram. C+R||C. Impedance Z.

Complex phasors - jω-method.

• Ex. 11.5 Komplex phasors. C+R||C.

Phasors in complex plane. Rotate the diagram - change of reference. Phasor. Notation. Phasors and use of complex numbers.

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Ex_phasor_en.pdf Building blocks of phasor diagram.

• Ex. 11.4 What’s inside the circuit?
• Ex. Phasor chart.
• Ex. 11.6 Phasor chart L||R+R. Step by step.
• Ex. 11.7 Phasor chart L+C||R. Step by step. - shows the importance of having the

correct lengths of phasors. jω-method.

• Ex. 12.2 Phasors for unknown circuit. jω-method.
• Ex. 12.6 Complex impedance R L C. calculate Z.
• Ex. 12.9 Complex Impedance, total current, current branching, voltage divider.

Methods: Complex conjugate or magnitude-phase.

• Ex. 12.7 R+C || L Derive the complex current I.
• Ex. 12.8 Derive the complex current I.

Resonance Le_resonance_en.pdf R L C impedance Z. Resonance when inductance and capacitance cancel each other.

• Ex. 13.1 Series resonance.

Higher voltage than supplied! Tesla coil. Q-value. OHM's law for series resonance. Phasor diagram for series resonance. Series resonance circuit Q-value and bandwith. Convenient formulas.

• Ex. 13.4 Series resonance circuit.

Ex 13.2 Parallel resonance. Higher current than supplied! Ideal parallel resonance circuit. Actual parallel resonance circuit.

• Ex. 13.2 Resonance frequencys for actual parallel resonance circuit.

Metal detector. Series- or parallel resistor. Transformation with the help of Q-value.

• Ex. Parallel circuit.

Induktiev sensor for bycycle. Resonance, jw-calculations. Ex_ACcircuits_en.pdf

• Ex. 12.3 jω-method RC-circuit
• Ex. 12.5 compare current for series and parallel connection.
• Ex. 12.1 complex expression for current I for R||C.
• Ex. Active power in impedance L+R.

Ex 13.7 SL accesscard. To measure Q-value?

• Ex. 12.4 Thevenin equivalent with inductor.
• Ex. Complex equivalent E0 and ZI.

CCP-unit frequency measurements. Le_frequency_en.pdf

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How to measure pulses? Pulses from numerous sensors. With the stream flow meter, Gear meter, Propeller and turbine Meter, Torque meter, Laser Scan Micrometer, Inductive pulse sensor, ABS- sensor, pressure sensor, Accurate measurement of f, Quantization. Direct frequency measurement, prescaler, period time measurement, multiperiod time measurement. Clock frequency accuracy. PIC-processor clock module. External crystal, external clockpuse generator, Atomic clockl?, RC-oscillator

• Timer1. watch-crystal 32768 Hz.
• Timer1. Number, EN-input. Prescaler.

How to read from a 16-bit "Freerunning" Timer1? How to write to a 16-bit "Freerunning" Timer1? CCP synchronized registers.

• CCP1CON. ECCP Capture modes

Frequency measurement program. Frequency measurment at lab. Why is the readings so incredibly precise? CCP-unit compare mode. Example ECU for combustion engines. Le_CCPcompare_en.pdf ECCP compare mode CCP1CON. Special event. Reset Timer1 and start AD. Sampling clock 1000 Hz. ECU Engine Control Unit. The need of ignition advance. The mechanical solution. Embedded Electronic’s solution! Sensors for speed and angle Angular position, Reference position, Current angular position, Rotational speed measurement. Sensors for motor load. Rolling road - Igniton advance table. Ignition. Carburetor or fuel injection. There will be more CCP-units needed. What Embedded Electronic Engine Control has managed to do CCP-unit PWM DC-motor control. Le_DCmotor_en.pdf Direct current motor BDC. Voltage constant. Voltage/angular speed. Commutator. The motor under load - Torque constant. Torque/current.

• Ex. Ex. An unknown motor?

PWM-voltage.

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Pulse operation free-wheeling. gear. PIC-processorn PWM. PWM H-bridge. TIMER2 servoupdate. Brushless DC motor. Electronic commutation, permanent rotor magnet, "trhre phase" stator winding. Torque motor - electrical downshift of the speed (and upshift of torque) Is this realy a DC motor? Simple RC-filter Le_filter_en.pdf A signal in reality. LP HP BP BS. RC-LP-filter with vectors. Voltage divider, Transfer function. RC-LP-filter with jω-method. Transfer function. Cut off frequency. Magnitude function and phase function. Graphs with Mathematica. RC Two sides of the same coin AD-converter LP-filter. RC HP-filter. Cut off frequency. Magnitude function and phase function. Wien bridge. Magnitude function and phase function. William Hewlett master thesis ... When are filters used? Speaker cross over filter. Analog or digital filter (passive/active speaker)? A "rolling" average is a digital LP-filter. Electrical interference. emc_en.pdf Differential amplifier. Differential mode/Common mode. Comparator is a Differential amplifier. Instrumentation amplifier - for weak signals in an interfering environment. Supression of electromagnetic interference. Twisted pair cable, Double-shielded cable, LP-filter, differential amplifier, decoupling of supply voltage. What is ground? A cable that supresses all electromagnet interference costs more than a PIC- processorer! LP-Filter. Transformer. Ex_filter_trafo_en.pdf Spänningsdelarens överföringsfunktion.

• Ex. 14.2 Transfer function
• Ex. 11.8 Phasor diagram for voltage divider.
• Ex. 11.8 Complex calculation.
• Ex. 14.7 Filter RLR
• Ex. 14.8 Filter LCR

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Transformers voltage and current ratio.

• Ex. 15.1, 15.2, 15.3 two values missing.

Inductive coupling.

• Ex. 15.8 three series connected inductors.

Ideal transformer Le_trafo_en.pdf Transformer. Voltage ratio. Magnetizing currrent is small. current ratio. Eddy current losses. EI-core. Toroid core.

• Ex. 15.4 Transformer.

Transforming impedances.

• Ex. Transforming capacitances.

Inductive coupling Interconnected flow Mutual inductance and Coupling factor Series with mutual inductance

• Ex. 15.7 Series connection

Measuring the mutual inductance? Variometer (to an antique radio) Variometer (to an antique radio) LVDT probe. XOR-gate finds the reference point. ATM will not distribute "double" bills. Ethernet contact. Le_ethernet_en.pdf Internet consists mostly of wired data communication equipment Isolation with transformers Signals and Interference - Commonmode and Differentialmode signals Balanced pulse transformer Common mode choke Data through a transformer? - Manchester code. Power over ethernet.