Mikroelektronika MIKROE-350 Fiche De Données

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
dim LCD_RS as sbit at PORTD.B2

LCD_EN 

as sbit at PORTD.B3

LCD_D4 

as sbit at PORTD.B4

LCD_D5 

as sbit at PORTD.B5

LCD_D6 

as sbit at PORTD.B6

LCD_D7 

as sbit at PORTD.B7

LCD_RS_Direction 

as sbit at DDRD.B2

LCD_EN_Direction 

as sbit at DDRD.B3

LCD_D4_Direction 

as sbit at DDRD.B4

LCD_D5_Direction 

as sbit at DDRD.B5

LCD_D6_Direction 

as sbit at DDRD.B6

LCD_D7_Direction 

as sbit at DDRD.B7

' End Lcd module connections

' OneWire pinout
dim OW_Bit_Write as sbit at PORTB.B2

OW_Bit_Read 

as sbit at PINB.B2

OW_Bit_Direction 

as sbit at DDRB.B2

' end OneWire definition

'  Set TEMP_RESOLUTION to the corresponding resolution of used
DS18x20 sensor:
'  18S20: 9  (default setting can be 9,10,11,or 12)
'  18B20: 12
const TEMP_RESOLUTION as byte = 12

dim text as byte[9]

temp 

sub procedure Display_Temperature( dim temp2write as word )
const RES_SHIFT = TEMP_RESOLUTION - 8

dim temp_whole as byte

temp_fraction 

text = "000.0000"

' check if temperature is negative
if (temp2write and 0x8000) then

text[0] = "-"

temp2write = 

not temp2write + 1

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CHAPTER 6