DORDT COLLEGE ENGINEERING DEPARTMENT
EMBEDDED MICROCOMPUTER SYSTEMS--EGR 304
(Spring 2014)

PROBLEM SETS

(Last update: 5/05/2014 2:29 pm)
PS
#   		Assigned Due Returned Assignment
11

4/22 5/01 (Nothing
to
return. Solutons
available
from
the
assignment
website) 		  Topics: LCD flat-panels, matrixing, A/D, D/A
 
  Read: Datasheet PCF8532 Universal LCD Driver
  See especially pages 3, 12, Section 7.3.3.1 on
  pages 14-15, Section 7.3.4 on pages 16-20.
  Please also scan the rest of the datasheet.
 
  Read this tutorial on d/a and a/d. be sure
  to click on the "next" buttons to read all ten
  pages of it.
 
  Do these worksheets on DAC and ADC. Feel free
  to "reveal" the answers after you have thought
  of your own answer. E-mail Prof. De Boer a
  note to tell him when you finished this
  assignment. (There is no need to send him the
  actual answers since they are already available.)
10

4/10 4/24 4/29   Read notes from class about position encoding
  including relative vs. absolute, two sensors,
  binary vs. grey code, v-scan, u-scan.
 
  Write up a design for a rotary relative
  encoder that has one degree of resolution and
  can keep track of direction of rotation and
  the position must not roll over before there
  are 90 full turns of the encoder's shaft in
  either direction from a reference position
  of zero degrees. Specify the number of teeth,
  the location of sensors and number of sensors,
  the connection to a micrcontroller including
  any needed logic and the number of I/O bits
  needed. Also spcify the word witdh needed to
  keep track of the relative position.
 
  Optional related links:
  Details on a particular relative encoder
  Wikipedia article: "Rotary encoder"
  Detail of a 13-bit grey code absolute encoder.
  Wikipedia on Single-track grey code
9

4/03 4/10 4/17   Topic: AC Motor Control via thyristors
  Read this tutorial on thyristors.
  And this on silicon controlled switches
  And this application note on triacs (and
  some other thyristors).
  And read about UJT and PUT's
  Do problems 2, 6, 8, 9, 13, 15, 16, 17, 18.
  Repeat as needed until you get it perfect.
  Send an e-mail to Prof. De Boer when done.
 
  Optional: Wikipedia on triacs
8

3/27 4/03 4/15   Read Freescale's tutorial on motors.
  (Click on the "launch" tab, then "Motor
  Principles" and then use the navigation
  buttons provided on the bottom of each page.)
  A few caveats about the above tutorial. . .
  In the illustration of the "Switched Rluctance"
  motor, the rotor will assume an induced
  magnetic field to oppose the applied magnetic
  field. This is not illustrated, probably
  because it might imply that the rotor is
  permanently magnetized, which it is not. It is
  just iron (or a steel alloy).
  In the illustration of the "AC Induction Motor"
  the coloration of the induced magnetic field
  in the rotor is backwards. According to Lens'
  Law, the induced field will oppose the applied
  magnetic feild from the stator. Thus the red
  (north) pole of the stator will face a green
  (south) pole on the rotor, just as in any other
  motor.
 
  Also read this motor tutorial and
  optionally this control tutorial from
  "Process Automation Control." Much of what is
  described in the control tutorial can now be
  done with microcontrollers.
 
  Do these problems on motors
7

3/06 3/27 4/14   Read Chapter 7 on "AVR Memories" in this
  datasheet. Note that the Arduino uses the
  "328P" microcontroller.
  Note, the above link only works on computers that have
  a connection to the Dordt College network and have
  the F: drive mounted. It also does not work in some
  browsers. If it does not work for you then download
  it directly from Atmel but this will be slower.
 
  Note errata in Ch. 7 on page 21. Register EEARH
  should show bit numbers labeled from 7 donwn
  to 0, not from 15 down to 8. Once that change
  is made, then bit 1 should be labeled as as
  "EEAR9" (not "–"). This is a read/write
  bit, "R/W" (not "R") which returns the stored
  data, "X" or "–", (not "0"). A corrected
  illustration is shown here.
  Do these problems on uC memory systems
6

2/25 3/06 4/14   Topic: Interrupts
  Read this overview on interrupts,
  and this handout on density and invervals
  and this on Arduino interrupt programming,
  Optional: article for a more detailed and more
  typical approach to programming interrupts for
  Atmel AVR processors (but non-Arduino) using
  the C language. (Some links only work after
  you have logged into courses@dordt.) Code
  supplements for the magazine article are
  available on the web in a zip file.)
 
  Do these problems on interrupts
  Errata: On problem 3.17 part (d) note that the
  only way for Tpi to be an average and a maximum
  at the same time is that the ISR takes exactly
  Tpi to execute every time it runs. This was the
  author's intent. (As opposed to allowing
  actual execution times to sometimes exceed Tpi.)
5

2/06 2/13 3/06   Read this handout on transmission lines.
  (This copy might print better on your printer.)
 
  Scan over these application notes from Texas
  Instruments on transmission lines. Read
  The section in AN-807 on the "tabular method."
  AN-806, and AN-807, and AN-808.
 
  Do 2.1 and 2.6 in the handout linked above.
 
  Optional: TI has purchased National Semi
  The application notes linked above were
  origianlly developed by National Semiconductor.
  There is more on National Semi in Wikipedia.
4

1/31 2/06 2/17   Read this Ethernet Tutorial. Also,
  browse the USB Standard version 2.0 on reserve
  in the library (It is on reserve. Ask a librarian
  for it by name, "Universal Serial Bus") or
  available from USB.org. If you download it
  from USB.org be sure to read the 2.0 version.
  (The 2.0 version superceeds the 1.0 version
  which is now withdrawn. However the 3.0 version
  is an addendum to the 2.0 version. It cannot
  stand on its own.)
 
  Take this twenty-question quiz.
  E-mail your quiz grade to Prof. De Boer.
  You are encouraged to repeat the quiz until
  you get a perfect grade. Turn in only your
  best grade. Also. . .
  do these short essays on USB.
 
  Optional: Books in Dordt's Library
  Optional: Wikipedia article Ethernet
  Optional Reading: USB article in Wikipedia
3

1/23 1/30 2/06   Read RS-232 in Wikipedia
 
  Do this problem:
  Plot voltage vs. time of the Tx line in RS-232
  for sending this text: "Z#" (without the
  quotation marks, with a capital "Z"). Assume
  ±12 V signal voltages, 53 kbaud, eight data
  bits, and one stop bit. Be sure to label your
  axes properly. An ASCII table can be found in
  many places, e.g. http://www.asciitable.com
  Note that the illustration in the Wikipedia
  reading does not have properly labeled axes.
  Specifically the the independent axis lacks
  scale and units.
 
  Optional: Listen to a Teletype machine.
  And see a Teletype machine connected to a
  Digital Equipment Corporation (DEC, a brand)
  model PDP-8/e computer. This computer could be
  booted "manually" via a bank of switches that
  allows the direct entry of machine code word-by
  word, executing each instruction as fast as the
  operator can enter the code. Wow, that's fast!
 
  Optional: Read about teleprinters.
 
  Optional: The entire RS-232 standard is
  available from Dordt's library. Interface
  Between Data Terminal Equipment And Data
  Circuit-Terminating Equipment Employing Serial
  Binary Data Interchange TK7887.5 .I57 1997
2

1/16 1/23 2/06   Topics: Parallel interfacing, I/O Drivers
  Read about multiplexing LED's and also
  multiplexing a keypad.
 
  Draw a schematic showing how to connect a two-
  digit common cathode 7-segment LED display
  and a 4x4 keypad to an Arduion Uno. There are
  many valid correct methods. You may be able
  to share rows or columns between the 7-seg.
  display and the keypad. You may search the
  Web for additional help on this assignment.
 
  Optional: (posted 4/08/2014) "epic" guide to
  keyboard internals.
1

1/14 1/16 1/23   Read "Embedded system" from Wikipeadia
  Browse "Getting Started with Arduino"
  Browse this datasheet.
  Do the introductory problems
  Note the chip number of the uC on the Arduino
  Uno is "ATMEGA328P-PV."
 
  Turn this problem set in electronically via
  courses@dordt. (Maximum file size is 1 MB)

Note 1) Homework solutions are usually available one or two class periods after the due date. Click the "returned date" on this page to access the solutions. If the "Returned" date is not a link (is black, not gold) then the solution is not yet posted. Check back later. If you click the link and get a login screen instead of the solutions, log in using your usual courses@dordt username and password. Then use the back icon (or alt-left-arrow on the keyboard) twice to get back to the link on this page and click the link again. The link only works when you are logged in to courses@dordt.

Note 2) Problems sets shown above with no "assigned" date are tentative. More problems might be added, expected due dates might change, but problems shown will eventually be assigned.

Note 3) If you are having difficulty reading the latest version of this page it may have to do with your browser's cached memory. Read this note on cached pages to solve the problem.