Presented by G4:Erik Church

Steve NyquistMichael GradyJennifer Miller

Highway Automation Simulation Kit Electronically Locating Lines

Project Goals

• Design and build a car that will model an automated highway system

• The car must stay on a line and avoid collisions

• Stay within a $200 limit• Optimally, the car will go wicked fast• Generate a course geared towards

sophomores that will reproduce similar results

The Motorola MC9S12DP256 Chip on the Axiom CML12S-DP256

Board

Why use the CML12S-DP256?

• Two 8 Channel Analog-To-Digital Converters

• Eight Pulse Width Modulation Channels

• Numerous I/O Pins• Coded in Assembly Language

Sharp-GP2D12 Distance Sensor

• Detects objects at a maximum distance of 80cm

• Increases voltage output as distance to the object decreases

Tape Detection

• We used IR Emitters and Detectors to locate the tape

• Dark colors absorb IR while bright colors reflect it

• IR is emitted toward the floor• Tile floor reflects IR back to the detector

while the tape absorbs it– If an IR detector reads high IR it is over the

floor– If an IR detector reads low IR it is over the

tape

IR Emitter and Phototransistor

• IR Emitter: Jameco id#112150• IR Phototransistor: Jameco id#112168• Paired an emitter with each phototransistor• Benefits to using two components:

– Cheaper (8 emitters/ 8 detectors $3.04)• Disadvantages:

– Needed an addition breadboard

IR Circuit

Sensor Array

– Emitters on the top row– Phototransistors on the bottom row

• 8 IR emitter/detector pairs• Close enough that at least one sensor detects

the tape at all times

R3 R2 R1 R L L1 L2 L3

Fro

nt o

f C

ar

Analog-To-Digital Converter

ATD Control Registers

• ATDxCTL2 – Contains the power-up bit

• ATDxCTL4 – Sets sample time and ATD clock prescaler

• ATDxCTL5 – Contains the multi-channel conversion bit– Must write to ATDxCTL5 to start a

new conversion• ATDxSTAT – Contains the sequence

complete flag

How to Read the ATD

• Once the sequence is complete, simply load ADRxy, where x is the ATD and y is the pin.

• Example: To read the last pin of ATD1, load ADR17.

The Futaba S3003 Servo(The Official Servo of CSE 480)

• Requires 5V source with ground connected to ground on board

• Controlled by Pulse Width Modulation– 20ms Period

• 1.152ms Duty for straight• 1.56ms Duty for full right• 0.808ms Duty for full left

Duratrax Electronic Speed Control

• Requires a 5V power source, just like the servo

• Controlled by PWM– Period of 20ms

• 1.664ms Duty for neutral• 1.04ms Duty for full speed reverse

– This most likely won’t be used

• 2.00ms Duty for full speed forward– G4 would not like to mention exactly how

fast full speed is but would like it to be noted that the SEB 133 lab is too small to make practical use of such alarming speeds

Motor

• Photon Speed 20 Turn Motor

• Lower number of turns means faster motor

• Most RC motors are 27 turn

Pulse Width Modulation

PWM Control Registers

• PWMCTL – Allows concatenation of channels

• PWMSCLA – Sets Clock SA– Clock SA = Clock A / ( 2 * PWMSCLA )

• PWMPERx – Sets the period of channel x– PWMx Period = Clock * 2 * PWMPERx

• PWMDTYx – Sets the duty for channel x– Duty Cycle = PWMDTYx / PWMPERx

Setting PWM to Correct Values• PWMSCLA = $02

Clock SA = 16MHz / ( 2 * 2 ) = 4MHz Clock SA Period = 0.25s

• PWMPER(0&1) = $9C40 = !40,000 PWM0 Period = 0.00025ms * 2 * 40000 = 20ms

• PWMDTY(0&1) = $0D00 = !3328 PWM0 Duty = 0.00025ms * 2 * 3328 = 1.664ms Duty Cycle = 1.664ms / 20ms * 100 = 8.32%

5V

0V

20ms

1.664ms

Overall Schematic

Inside IR Sensors

Distance Sensor

Outside IR Sensors

Horn (Buzzer)

Servo

ESC

Blinkers

ATD00 ATD01 ATD02 ATD10 ATD11 ATD12 ATD13 ATD14 ATD15

PJ0 PWM4&5 PWM0&1 PWM2 PWM3

Main Program

• INIT – Initializes ATDs and PWM Channels

• DISTANCE – Reads the distance sensor and adjusts speed as needed

• TRACK – Reads the IR sensors and turns car as needed

Start

INIT

Set ATD0CTL5

SCF?

DISTANCE

TRACK

No

Yes

Distance Subroutine

• BRAKE – Stops the car, turns on brake lights and honks the horn

Distance

Read Distance Sensor

> $0E?

Turn off horn and Brake Lights

BRAKE

Return

Yes

No

• Straight – Sets servo straight

• VRight – Sets servo to veer right

• VLeft – Sets servo to veer left

• OUTSIDE – Checks if other IR sensors detect tape

Track SubroutineTrack

Read in Left Inner IR Sensor into A

Read in Right Inner IR Sensor into B

Left on Black?

Right on Black?

Right on Black?

OUTSIDE

VRight VLeft

STRAIGHTYesYes

Yes

NoNo

No

Return

Outside SubroutineOutside

Set ATD1CTL5

SCF?

Load L1

On Tape?

Load R1

On Tape?

L1-Turn

Load L2

On Tape?

R1-Turn

R2-Turn

L2-Turn

Load R2

On Tape?

Load L3

On Tape?

R3-TurnL3-Turn

Load R3 On Tape?

NoTrack

Return

No

No

No

No

No

No

No

Yes

Yes

Yes

Yes

Yes

Yes Yes

Budget Sharp GP2D12 Infrared Ranger: $$$8.258 IR Phototransistor (id#112168): 0$$1.92 (bulk)

8 IR Emitters (id#112150): 0$$1.12 (bulk)

Car Kit (includes)Car, ESC, Motor, Frame, Wheels, Other: $$58.88

Futaba S3003 Servo: $$$9.996-cell battery: $$$8.32 (bulk)

Breadboard: $$$3.90 (bulk)

3 9v Batteries: $$$1.65 (bulk)

3 Battery Connectors: $$$0.75 (bulk)

2 LEDs: $$$0.22 (bulk)

Resistors and Wires: $$$0.25 (bulk)

2 5V Voltage Regulators: $$$0.44 CML-9S12DP256: $115.00

 Total: $210.69

Things We Could Have Changed

• Use Rechargeable Batteries• Utilize the LCD and Keypad that

came with the DP256 board• Use Better Distance Sensor/Better

Braking System• Use Better Horn

Ideal Car For Sophomore Design

• OOPIC board: Sophomores will already know VB from CSE141

• Create their own frame on Campus: More educational than ordering a kit

• Select motor based on requirements of car

• H-Bridge instead of ESC: Cheaper• Separate IR emitter/detector

Main Program Assembly Code

START:

jsr INIT

STRAP:

ldaa #ADMODE

staa ATD0CTL5

SPIN:

brclr ATD0STAT,SCF,SPIN

jsr Distance

jsr Track

bra STRAP

Distance Subroutine Assembly CodeDistance:

ldaa ADR02H

movb #$00, HALTFLAG

cmpa #$0E

bhs BRAKE

movb #$00, PTJ

movb #$00, PWMDTY2

movb #$00, PWMDTY3

rts

BRAKE:movb #$01, PTJmovb #$FF, HALTFLAGmovb #$FF, PWMDTY2movb #$FF, PWMDTY3movb #$0C, PWMDTY0movb #$A0, PWMDTY1rts

Track Subroutine Assembly CodeTrack:

movb #$00, NOTRACKFLAG ldaa ADR00H ldab

ADR01H cmpa#$A0 bhi

ONLEFT cmpb #$A0 blo NOTONRIGHT jsr Vright

rtsNOTONRIGHT:

jsr OUTSIDE rts

ONLEFT: cmpb #$B0

bhiONBOTH jsrVleft rts

ONBOTH: jsr STRAIGHT rts

Outside Subroutine Assembly CodeOUTSIDE:

ldaa #ADMODE staaATD1CTL5

SPIN2: brclrATD1STAT, SCF, SPIN2ldaa ADR10H cmpa #$90

blo NOTONL1 jsr L1

rts

NOTONL1: ldaaADR11H cmpa #$B0 blo NOTONR1 jsrR1 rts

NOTONR1: ldaaADR12H cmpa #$C0 blo NOTONL2 jsrL2 rts

NOTONL2: ldaaADR13H

cmpa #$B0 blo NOTONR2 jsr R2 rts

NOTONR2: ldaaADR14H

cmpa #$E0 blo NOTONL jsr L3 rts

NOTONL3: ldaaADR15H

cmpa #$B0 bloNOTONTRACK jsrR3 rts

NOTONR3: jsrNOTRACK

rts

Turning Assembly Code

L1: movb#$07, PWMDTY4 movb#$D6, PWMDTY5 ldaa#$FF cmpaHALTFLAG beq L1RETURN movb#$0D, PWMDTY0 movb#$C8, PWMDTY1 movb#$18, PWMDTY3 movb#$00, PWMDTY2

L1RETURN: rts