Sonar and IR Ranging with the Atmel AT90S8515

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Product image for Devantech SRF04 Ranger

Introduction
Source Code - AT90S8515 with SRF04
Source Code - AT90S8515 with GP2D02
Comments

Introduction

The Atmel Corporation makes the popular AVR family of microcontollers. These devices have an 8-bit RISC core and Flash memory for in-system programming. Two example programs for the AT90S8515 microcontroller are listed below. They show how to use some common ranging devices. Both programs were developed with the BascomAVR Basic compiler .

Contents

Source Code - AT90S8515 with SRF04

The following program shows how to use a Devantech SRF04 Ultrasonic Rangefinder with the AT90S8515. Pin connection info may be found in the comments and code. The user must design any additional circuitry that may be needed.

$sim 'REMOVE the above command for the real program !! '$sim is used for faster simulation '************************************************** ' filename: atSRF04.bas ' Devantech SRF04 Ultrasonic Range Detector ' Test example program for Atmel 90S8515 MCU. ' By Earl Bollinger Jan 21, 2002 ' earlwbollinger@attbi.com '************************************************* 'LCD to AVR 8515 pinouts '1 GND '2 VCC +5 '3 Contrast 10k from Vcc to Gnd wiper in between '4 RS PortD.2 '5 RW Gnd '6 E PortD.3 '7 D0 Gnd '8 D1 Gnd '9 D2 Gnd '10 D3 Gnd '11 D4 PortD.4 '12 D5 PortD.5 '13 D6 PortD.6 '14 D7 PortD.7 Config Lcdpin = Pin , Db4 = Portd.4 , Db5 = Portd.5 , Db6 = Portd.6 , Db7 = Portd.7 , E = Portd.3 , Rs = Portd.2 Config Lcd = 24 * 2 'configure lcd screen Dim Dist As Word Dim D As Word D = 9 'cheap conversion factor for inches, cm's, whatever 'Devantech UltraSonic SRF04 Rangefinder pinout ' +5v supply 'Echo Output to Port A pin3 'Pulse trigger input to Port A pin2 'Do not use 'Ground 'Port A pin 2 for Pulse trigger output to device 'Port A pin 3 for echo input from device Ddra = &B11011111 Porta.2 = 0 Dist = 0 Mainloop: Cls Waitms 400 Lcd "Sonar Range = " Pulseout Porta , 2 , 20 'very sensitive to pulsewidth Pulsein Dist , Pina , 3 , 1 Dist = Dist / D Lcd Dist Wait 1 Goto Mainloop End

Contents

Source Code - AT90S8515 with GP2D02

The following program shows how to use a Sharp GP2D02 Infrared Ranger with the AT90S8515. Pin connection info may be found in the comments and code. The user must design any additional circuitry that may be needed.

$sim 'REMOVE the above command for the real program !! '$sim is used for faster simulation '************************************************** ' filename: atGP2D02.bas ' Devantech Sharp Infrared GP2D02 Object Detector ' Test example program for Atmel 90S8515 MCU. ' By Earl Bollinger Jan 21, 2002 ' earlwbollinger@attbi.com '************************************************* 'LCD to AVR 8515 pinouts '1 GND '2 VCC +5 '3 Contrast 10k from Vcc to Gnd wiper in between '4 RS PortD.2 '5 RW Gnd '6 E PortD.3 '7 D0 Gnd '8 D1 Gnd '9 D2 Gnd '10 D3 Gnd '11 D4 PortD.4 '12 D5 PortD.5 '13 D6 PortD.6 '14 D7 PortD.7 Config Lcdpin = Pin , Db4 = Portd.4 , Db5 = Portd.5 , Db6 = Portd.6 , Db7 = Portd.7 , E = Portd.3 , Rs = Portd.2 Config Lcd = 24 * 2 'configure lcd screen Dim X As Byte Dim Dist As Byte Dim D As Byte X = 255 D = 10 'cheap conversion factor for inches, cm's or whatever 'Devantech Sharp GP2D02 Infrarwed Object Detector pinout 'pin 1 (black) Ground 'pin 2 (Green) Vin pulse input drive 'pin 3 (red) VCC +5v supply 'pin 4 (yellow) Vout serial data out 'Port A pin 0 yellow data input from IR device 'Port A pin 1 green output wire to IR device Ddra = &B10111111 Porta.1 = 1 Dist = 25 X = 255 Mainloop: Cls Waitms 400 Lcd "Infrared Range = " Porta.1 = 0 Waitms 70 Porta.1 = 1 Shiftin Pina.0 , Porta.1 , Dist Dist = X - Dist 'Dist = Dist / D Lcd Dist Wait 1 Goto Mainloop End

Contents

Comments

Thanks go to Earl Bollinger for contributing these code examples.

Revision History:

2002-03-22: Page Created