Mikroelektronika MIKROE-742 데이터 시트

This example reads the temperature using DS18x20 connected to pin PORTB.2. After reset,
MCU obtains temperature from the sensor and prints it on the Lcd. Make sure to pull-up PORTB.2
line and to turn off the PORTB leds.

program OneWire;

// Lcd module connections
var LCD_RS : sbit at PORTD.B2;

LCD_EN : 

sbit at PORTD.B3;

LCD_D4 : 

sbit at PORTD.B4;

LCD_D5 : 

sbit at PORTD.B5;

LCD_D6 : 

sbit at PORTD.B6;

LCD_D7 : 

sbit at PORTD.B7;

LCD_RS_Direction : 

sbit at DDRD.B2; 

LCD_EN_Direction : 

sbit at DDRD.B3;

LCD_D4_Direction : 

sbit at DDRD.B4; 

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- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 6

procedure Ow_Write(par: byte);

Nothing.

Writes one byte of data via the OneWire bus.

Parameters : 

- 

par

: data to be written 

Devices compliant with the Dallas OneWire protocol.

Global variables : 

- 

OW_Bit_Read

: OneWire read line 

- 

OW_Bit_Write

: OneWire write line. 

- 

OW_Bit_Direction

: Direction of the OneWire pin 

must be defined before using this function.

// OneWire pinout
var OW_Bit_Read : sbit at PINB.B2;     
var OW_Bit_Write : sbit at PORTB.B2;   
var OW_Bit_Direction : sbit at DDRB.B2;
// end of OneWire pinout

// Send a byte to the One-Wire Bus
Ow_Write(0xCC);