Presentation on theme: "Embedded Computer Systems Elec471 Welcome remarks and Class Overview Associate Professor Cap’n Tim Johnson, PE."— Presentation transcript:
Embedded Computer Systems Elec471 Welcome remarks and Class Overview Associate Professor Cap’n Tim Johnson, PE
Welcoming Remarks In your previous class, Elec 244 Digital Systems, we learned about digital logic and the building blocks for memory. You were introduced to a microcontroller and ran small computer programs to control LEDs. In this class we will learn about systems which control real processes and build basic designs. At the process’s core is a microprocessor running a program.
Welcoming Remarks In this course we learn about and use analog to digital conversion (ADC) hardware and how to control the operation of a system. All these designs run C code so we’re going to become better at all aspects of coding by practice. No systems is of any use unless it’s serving a distinct purpose. We’re going to learn how to use mathematics to model the process and determine how well we serve that purpose.
Welcoming Remarks Conclusion Everything you learn in this class is directly useful in your junior and senior design classes. All you have to do is: – Come to class – Pay attention and take notes – Do the homework – Do the labs – Take some tests – Think about what you’re learning and how it’s used.
Why would I say… …think about what you’re doing and how it’s used? The answer is: Time and Materials We only have 1 semester for this course. We only have a few practical systems. So it’s the process that’s the same and you just substitute out different parts. The parts are the peripherals (I/O in & out), the processor, the memory, and the interfaces. I/O in are sensors. The I/O’s out can be a communication bus, display devices, or memory.
What process? A real-time process takes constant reading of its environment, let’s assume its a beaker of water that needs to be boiling. We need several things to have this happen: A beaker Water Heat Time source Process description: the water enters a container, turn on the heat, wait until the water boils, turn the heat off, and move the water to its intend use.
Let’s automate the process Verify the beaker is in position using a simple switch or a break in an optical signal. Apply voltage to the motor driving the valve to open. A limit switch in the valve opens the voltage to the motor turning the motor off. A float switch or other device detects the necessary water level and signals the motor to reverse the polarity causing the motor to close the valve. A different limit switch in the valve opens the voltage to the motor turning the motor off.
Automated Process part II The heating source is next turned on. Depending on the type of heating source there are different ways of turning the heat on and off. Is the water is boiling yet? There are several methods of determining this information. A thermocouple will give a temperature readout that varies directly with the temperature. This information has to be converted to digital data to be read. Whatever is used has to turn the heat off when the boiling point is reached and signal that the process is complete.
Function Block Diagram The heating element generates heat due to the current flowing from the AC source thru the relay (closed thru when the I/O output voltage is ON). The thermocouple absorbing the heat causing a smaller measureable current to flow in its output wiring. The ADC converts the current to a voltage then converts the voltage to a digital output. The code evaluates the digital output for the temperature setting the I/O register ON or OFF controlling the relay.
Sample Process In the above process the multi-meter converts the current flow from a thermocouple connected to a soldering iron to an analogue voltage reading and off to the side is a computer running LabView that turns the power supply on and off.
Transition Slide This course this year will be different from “normal”. I’m hoping to have most of the lectures posted on blackboard. Grading will be done on blackboard. You’re only going to learn as much as you are interested in. My job is to evaluate your learning. The syllabus is posted on my website: www.myweb.wit.edu/johnsont
Weekly expectations You have viewed whatever power point has been posted. You have “tested” yourself. You have completed a lab or portion of a lab associated with the lecture. You have added vocabulary to a list of new words you have learned or plan to learn. You are capable of discussion and/or have questions related to this or previous learning.
Weekly Journal You have added your ideas/discussion/ questions to your journal. You have written up the weekly lab. Hand in a copy to me of your journal entry. – What you did. – What your results were. – What you thought of the lab. State whether or not the lab exemplify the lecture or a specific lab learning objective? Whether you had trouble in the lab and what you did to attempt a solution. What your solution was.
Lab Report Should have a cover page Should include all names of person present during the lab that participated in doing the lab. Should have the section that the lab is for. Should contain original writing amount to approximately 100 words or more. Copy Word Count into your lab to verify. Screen shot of your work if done on a computer. Explanations of what you did as mentioned on previous slide.
FAQ Q#1 What do I really want? Oh, I forgot to mention you really have to get down with software. I’m firmly convinced the future of hardware is software. So, a software guru called Bucky Roberts is going to teach you everything you wanted to know. He has 15 videos on C programming. Know them. When the class is ready, I’ll test you on your knowledge. His lessons are located here: http://thenewboston.org/tutorials.php http://thenewboston.org/tutorials.php We’ll have more lessons as the semester goes on.
FAQ Q#2 What do we doing this week? We’re going to start learning LabView. Immediately following the Q&A session for this power point. There will be instructions in the power point regarding homework for LabView. The lab will be Interfacing LabVIEW with Test Bench Instruments found on my website.
Assignment #01A Draw a FBD (function block diagram) for a simple bottle opener that provides an audible message upon activation. Here’s a link to a representative design: http://www.youtube.com/watch?v=_qFFkO6NcKE http://www.youtube.com/watch?v=_qFFkO6NcKE Here’s a link to MSP430 microcontrollers: http://www.ti.com/lit/sg/slab034u/slab034u.pdf http://www.ti.com/lit/sg/slab034u/slab034u.pdf Here’s a link to a somewhat useful DAC tutorial: http://www.eetimes.com/electrical-engineers/education- training/tech-papers/4207829/A-DAC-Applications-Tutorial http://www.eetimes.com/electrical-engineers/education- training/tech-papers/4207829/A-DAC-Applications-Tutorial