EECEC 322 Lab 7 and Lab 8

1
EE/CEC 322 Lab 7 and Lab 8

• 8051 Stepper Motor
• Part 1 no report
• Part 2 report Due 3/6/08
• This report counts 20 points
• Please Note Lab 8 is scheduled for Tuesday March
  4th 600 PM

2
Objective

• Operate a Stepper Motor using the 22V10 as the
  Step State Machine use the 8051 to produce the
  step clock for the 22V10 and control direction.
• Build the 22V10 code in VHDL to operate the
  stepper motor
• Use Lab 5 for this
• Use the 8051 to generate a variable rate step
  clock
• Use Timer 0 for this
• Build a command parser that responds to the
  commands
• R (or r) turn right
• L (or l) turn left
• S (or s) stop
• numbers 1-0 to set step speed
• 1 1 step per second
• 2 2 steps per second
• 0 10 steps per second
• Once per second, output to the PC, the stepper
  position in counts

3
Prelabs

• Prelab 7 design the software (C) required for
  the Lab 7 portion of the deliverables (slide 8)
• Prelab 8 design the software solution required
  for the Lab 8 portion of the deliverables (slide
  9)

4
Background

• Lab 3 we wrote and tested VHDL code for operating
  a stepper motor assuming the state transition
  clock and direction inputs were provided by the
  8051
• Lab 5 we operated the stepper motor but without
  enable and direction control. We will need to
  add these capabilities
• Lab 6 we built a serial interface we will need
  to expand the serial capability

5
PLD Programming (this was done in lab 5)

• If you have your PLD code from Lab 5, nothing
  further will need to be done here
• The stepper motors have phase B and Phase C
  reversed in the wiring
• You must reverse these two phases in VHDL code
• The disable state must output phases A-D the
  logic 1 in order to shut off all the motor
  windings
• The outputs of the 22V10 (Phases A-D) are
  inverted before they reach the stepper driver
  transistors
• Your VHDL state outputs must also be reversed

6
8051 programming

• Upon reset have the 8051 print an introductory
  message to the PC
• This might include
• your name
• date
• lab number
• Program the Timer 0 ISR.
• Lab 5 used an int to count interrupts, here you
  will need a variable (value set by the command
  parser) to determine when to toggle the clock pin
  
• Program the serial interrupt to accept commands
  and send messages
• The code that initiates sending status to the PC
  should be in main()
• The command parser also should go in main()
• You will need a function that converts the
  stepper position represented as an int, to an
  ASCII string that is printable to the PC

7
Needed code

• From class, most of what you need is available
• You will need a command parser An example has
  been provided in class
• You will need a function that converts a signed
  integer to an ASCII string, much like printf()
  does when programming a PC console program.
  Again an example exists from class

8
Deliverables

• Lab 7 portion
• Design a software solution for the serial
  interrupt, timer interrupt, and main()
• main() will require a
• command parser
• Send Status once per second
• express these solutions in the form of flow
  charts
• Demonstrate your serial communications including
  your binary to ASCII conversion routine

9
Deliverables Continued

• Lab 8 portion
• complete the lab by adding the stepper
  functionality and all the command options
• Demonstrate proper operation of the Stepper Motor
• Write your report include your deliverables
  from the Lab 7 portion
• Include your design documentation with your
  report
• The lab report will count 20 points (2 labs)