DHT22... code

[nortepic]

i have this code for dht22...it is bases in the libraries of another forum

it is not very good, but i'm new in ccs, so i think that for this time it's ok :P

#include <18f4550.h> //PIC utilizado
#device adc=10
#fuses HS,NOWDT,NOPROTECT,NOLVP,NODEBUG
#use delay(clock=20M)
#fuses HSPLL,NOWDT,NOPROTECT,NOLVP,NODEBUG,USBDIV,PLL5,CPUDIV1,VREGEN
#use delay(clock=48M)
#build (reset=0x1000,interrupt=0x1008)
#org 0x0000,0x0FFF{}
//#use i2c(Master,slow,sda=PIN_A4,scl=PIN_A5)
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7)
#include "dht22.c"
#include <LCD420.c>

void main(){
int16 lux;
float dhthum, dthtemp;
setup_adc_ports(AN0|VSS_VDD);
setup_adc(ADC_CLOCK_INTERNAL);
EXT_INT_EDGE(H_TO_L);
lcd_init();
lcd_putc("\fDHT22");
delay_ms(500);
printf(lcd_putc,"\f");
lcd_gotoxy(1,1);
printf(lcd_putc,"Control");
lcd_gotoxy(1,2);
printf(lcd_putc,"Temperatura");
lcd_gotoxy(1,3);
printf(lcd_putc,"y Humedad");
dht_init();

delay_ms(300);
lcd_putc("\f");
while(true){
set_adc_channel(0);
delay_ms(1);
lux=read_adc();
delay_ms(10);
leer_dht22(dhthum, dthtemp);
delay_ms(10);
delay_ms(1);
lcd_gotoxy(1,1);
printf(lcd_putc,"Temp= %f %cC", dthtemp,223);
lcd_gotoxy(1,4);
printf(lcd_putc,"Hum= %f %%",dhthum);
delay_ms(2000);

[ezflyr]

Hi,

What *could* be the problem, or what *is* the problem? Big difference!

The fact is that nobody here wants to debug a Proteus project - it's pointless!

So, you should try the DHT-22 driver found in the code library and see if that works! In general, you shouldn't be re-inventing the wheel anyway!
_________________
John

If it's worth doing, it's worth doing in real hardware!

[temtronic]

John's tag line is the TRUTH!!

Us older guys KNOW Proteus is busted, full of errors and faulty DRCs and never, ever use it.

Basic trouble shooting says
1) get the PIC 'up and running' the 1Hz LED program. This MUST be done to confirm hardware is valid,fuses are correct and the PIC clock is running at the correct speed.

2) get the PIC to say 'Hello PC !' or 'Hello LCD !'. Again this MUST be done to confirm hardware and software is correct.

3) read the device datasheet, look at the timing diagrams ! 'Play computer' and confirm every step, every timing(delay) is proper for THAT device.

4) copy old program to a new one, make change to the new one NOT the old one,then compile the new one, test. and repeat. It's too easy to make 2 or 3 'small' changes to working code and then nothing works ! Yes, you can end up with 30-40-77 versions BUT who cares? Delete all but the last 3 when your project is complete. Add comments to every line of code,they cost nothing but will tell you 1 day - 1 month from now WHAT it does.

5) re: drivers. NEVER edit an original driver! Copy as 'my_driver.c' and use it, modify if needed. Again,editing a working driver can be disasterous, costing you a LOT of time trying to decide why it doesnt't work...it did before !

Jay