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τ rise size 12{τ rSub { size 8{ ital "rise"} } } {} = .13 secs
τ fall size 12{τ rSub { size 8{ ital "fall"} } } {} = .23 secs

We used the average of these readings, i.e., (0.13+0.23)/2 = 0.18  and rounded to 0.2 sec. 

Ω s E s = K m 1 1 + m Ω s E s = K m 1 1 + . 2s size 12{ matrix { { { %OMEGA left (s right )} over {E left (s right )} } =K rSub { size 8{m} } { {1} over {1+sτ rSub { size 8{m} } } } {} # dlrarrow {} # { { %OMEGA left (s right )} over {E left (s right )} } =K rSub { size 8{m} } { {1} over {1+ "." 2s} } {}} } {}

Real-time system design

The system design comprises two parts:

  1. Simulation, to determine the parameters of the Speed Control Transfer Function
  2. Hardware Design of the interface circuit.


The speed control is a PID controller. A DC motor model (Figure 14) was created. The complete control loop model is shown in Figure 15. Figure 16 shows the parameters chosen for the PID controller.

DC Motor Model
Loop Control Model
PID Controller Parameters

Hardware design

The connection between the eZDSP and the Motor Kit requires a dedicated interface circuit, implementing the Low Pass Filter (used for the Digital to Analog conversion) and adapting the voltage levels at the eZDSP (0 to 3V) to those of the DC Motor Kit (0-15V). The various signal types and their voltage range are shown in .

The interface circuit contains two blocks. The first is LPF with an amplifier (shown in Figure 18), connected between the PWM output and the servo amplifier input. The second block is an attenuator (shown in Figure 19) connected between the tachometer output and the Analog to Digital Input of the eZDSP.

Signal Types and Voltage Levels

LPF + Amplifier Circuit
The Inverting Amplifier with LPF

Real time implementation

The control loop was implemented in the eZDSP F2812 as shown in Figure 20. The PID controller obtained in the previous chapter was implemented in the DSP. The environment is shown in Figure 21.

The real-time implementation model will be created from the "DC Motor Speed Control via RTDX" SIMULINK demo. In the original demo model the loop is closed by QEP block, we will use a tachometer connected to the Analog to Digital Converter module for speed measurement.

The Model and its subsystems are shown in Figures Figure 22, Figure 23 and Figure 24.

LPF + Amplifier Circuit>


  1. Navigate into the following directory:


  1. Copy the following files into your working directory:
    • c2812speedcontrolDC.mdl
    • runc2812speedcontrolDC.m
    • runc2812speedcontrolDC.m
    • Open the c2812speedcontrolDC.mdl model and save it as "DCMotorControlc2812.mdl"(please refer to Figure 21 The model is shown here after deleting the “Info” box. ).
    Real-Time Implementation Model
  2. Double-click the Speed Correction Block, and you will see:
    Figure 22: Speed Control
  3. Configure the C28x PWM block as follows:
    Figure 23: PWM Configuration
  4. Configure the "PID Controller" block as follows:
    PID Configuration
  5. Double-click the Speed Correction Block, and you will see:
    QEP Based Speed Measurement
  6. Delete the selected blocks and replace them by the ADC block from Open the ADC block from the C281x Chip support group from the C2000 Target Preferences, and connect is as follows:
    ADC+Tachometer Based Speed Measurement
  7. Now the model is ready for real-time, we need however to update the MATLAB script file. Open the “Model Properties” from “File” menu. Change the PostLoadFcn callback to runc2812speedcontrolIDC, as shown:
    Model Callback
  8. The next step is to change the original PWM range (up to 64000) to the desired range (up to 4000). Open the “speddControlIDCLoop.m” file with the MATLAB editor, an change on line 48 the command: cycle = (double(pid).*100./64000);to cycle = (double(pid).*100./4000); Please refer to the following picture:
    Changing the PWM range
  9. Activate the motor
  10. Activate CCS.
  11. Click the Build/Reload&Run box, the following window should appear:
    Speed Control GUI
  12. You may change the speed of the motor using the slider in the right hand side and the “Apply” button.


  1. "eZdspTM F2812 Technical Reference", Spectrum Digital, 2003 (External Link)
  2. David M. Alter, " Using PWM Output as a Digital-to-Analog Converter on a TMS320F280x", TI Application Report SPRAA88 , September 2008 (External Link)

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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