Transcript Introduction to Interfacing Projects

Introduction to
Interfacing Projects
Nareen Khan
Using Turing
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Command to send data to parallel port
parallelput (x : int)
The command sends 1 byte of data to the
parallel port at a time.
Using 1 byte (8 bits) we can represent
28=256 different states.
The 8 bits are sent along the Data pins on the
parallel port (Pins 2-9, D0-D7)
Understanding the Parallel Port
Data Lines (D) used for output.
13 12 11 10 D7
9 D6
8 D5
7 D4
6 D3
5 D2
4 D1
3 D0
2 1
25 24 23 22 21 20 19 18 17 16 15 14
Grounds
Status Lines (S)
used for input.
Control Lines (C)
may be used for
input / output
Binary on the Parallel Port
0
1
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parallelput(0)
parallelput(1)
parallelput(37)
parallelput(255)
0
1
0
1
0
1
0
1
0
1
0
1
0
1
The integer parameter is
translated into binary and
each bit corresponds to
one of the data pins on
the parallel port.
Unsure of your conversions? Try this utility.
What does the circuit look
like?
220Ω
Voltage
from
parallel
port
Pin 2
Pin 18
parallelput(0)
Switch is open, no
path, LED off
parallelput(1)
Switch is closed,
path exists, LED on
Breadboard Basics
Connected
vertically in
blocks of 5
Connected
horizontally
Light Emitting Diodes
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LED’s will only work if
they are installed in
the right direction.
Here are three ways to
tell which is the
negative (-’ve) lead.
1) –’ve lead
is shorter
Light Emitting Diodes
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LED’s will only work if
they are installed in
the right direction.
Here are three ways to
tell which is the
negative (-’ve) lead.
2) Internal
segment is
larger
Light Emitting Diodes
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LED’s will only work if
they are installed in
the right direction.
Here are three ways to
tell which is the
negative (-’ve) lead.
3) Flat side
on lip
Top View
Wiring an LED
+’ve, Long Lead
Project Samples
Traffic
Intersection
Traffic Intersection
Traffic Intersection
Student GUIs
Student GUI’s
The Traffic Intersection Project
Steps:
1) Wire six LED / resistor pairs on breadboard
2) Attach the wires to your model
3) Write your program
4) Enjoy hours of staring at the lights change
Step 1 – Wiring the lights
+’ve, Long Lead
-’ve, Short Lead
Step 2 – The D-Sub Connector
1)Attach your wires to the crimp pins.
2)Be sure to press the clamps down
tight on the wire.
3)Push the crimped pin into the D-Sub
Connector (it’s a tight fit).
4)Repeat for the other 7 wires.
Step 1 – Wiring the lights
Step 1 – Wiring the lights
Test your interface
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Once you’ve got the wires connected to the
parallelport, you can test the interface.
Try :
parallelput(255)
This should turn on all your lights.
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Sample Program #1
Sample Program #Step 1 –
Wire Wrapping
Make Use of the Tri-State
Buffer – See the Handout
Making The Turing Program 1
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Make a Program Header
%
%
The "trafficIntersection" program
%
Course Code: ICS 3M1
%
Instructor: Your Teacher
%
Date: April 25, 2007
%
Initial Release
%
% This Program simulates a traffic intersection in graphics. It can also properly
drive the actual
% intersection by use of a parallel port and binary outputs.
Making The Turing Program 2
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Create a User Defined Data Type
type trafficState: % data type trafficState will store various components of traffic
states.
record
timeWait : int % var for the time in that state
binState : int % binary value of that state (more details see pin output state
table
NSPic : string % var for the state of the NS light
EWPic : string % var for the state of the EW light
end record
Making The Turing Program 3
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Create a User Defined Data Type
drawfillbox(0, 0, maxx, maxy, 54) % code for background colour
% The 6 states are declared as an array of trafficState data type
var trafficPattern : array 1 .. 6 of trafficState
% Below contains the value of each of the states
% timeWait: Green light - 5 sec.
%
Yellow light - 2 sec.
%
Both red light - 1.25 sec.
% binaryStates in decimal: NS green - 1
%
NS yellow - 2
%
NS red - 4
%
EW green - 8
%
EW yellow - 16
%
EW red - 32
Making The Turing Program 4
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Note the binary States listed below
drawfillbox(0, 0, maxx, maxy, 54) % code for background colour
% The 6 states are declared as an array of trafficState data type
var trafficPattern : array 1 .. 6 of trafficState
% Below contains the value of each of the states
% timeWait: Green light - 5 sec.
%
Yellow light - 2 sec.
%
Both red light - 1.25 sec.
% binaryStates in decimal: NS green - 1
%
NS yellow - 2
%
NS red - 4
%
EW green - 8
%
EW yellow - 16
%
EW red - 32
Making The Turing Program 5
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Then Define Each Traffic Pattern in this
manner…
%NS Green EW Red
trafficPattern(1).timeWait := 5000
trafficPattern(1).binState := 1 + 32
trafficPattern(1).NSPic := "trafficgreen.bmp"
trafficPattern(1).EWPic := "trafficred.bmp“
%NS Yellow EW Red
trafficPattern(2).timeWait := 2000
trafficPattern(2).binState := 2 + 32
trafficPattern(2).NSPic := "trafficyellow.bmp"
trafficPattern(2).EWPic := "trafficred.bmp“ etc…
Making The Turing Program 6
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Create a Procedure
% procedure for loading the pictures in the different states
procedure drawIntersection (NSFile : string, EWFile : string)
Pic.ScreenLoad (NSFile, 250, 250, 0)
Pic.ScreenLoad (EWFile, 100, 150, 2)
Pic.ScreenLoad (NSFile, 250, 50, 0)
Pic.ScreenLoad (EWFile, 400, 150, 2)
end drawIntersection
Making The Turing Program 7
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Finally, cycle through the lights…
% Loop to make the cycle continuous
for i : 1 .. 4
% Loop for each of the traffic states and giving drawIntersection the images
to change
for j : 1 .. 6
drawIntersection (trafficPattern(j).NSPic , trafficPattern(j).EWPic)
parallelput (trafficPattern(j).binState) % send info to parallel port
delay (trafficPattern(j).timeWait) % delay the amount of milliseconds
indicated in traffic state
end for
end for
Making The Turing Program 8
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Make Sure You Have These Graphics Files