I have built my first Arduino project - the Temperature controlled fan from the code and schematic on this site.
https://circuitdigest.com/microcontroller-projects/automatic-temperature...
After some time I got past the library include problem to now have this:
sketch_dec26a:6: error: 'dht' does not name a type
dht DHT;
^
C:\Users\wfene\OneDrive\Documents\Arduino\sketch_dec26a\sketch_dec26a.ino: In function 'void loop()':
sketch_dec26a:39: error: expected unqualified-id before '.' token
DHT.read11(dht_dpin);
^
sketch_dec26a:40: error: expected primary-expression before '.' token
int temp=DHT.temperature;
^
exit status 1
'dht' does not name a type
Any help to clear this hurdle would be appreciated so I can put this to work on my solar furnace !
Did you use the same program given in that link or did you make any modifications? I tried the same program from the link and it compiled properly for me.
Its always a good practice to paste your code in the forum rather than pointing it to a link. This way people can help you a bit more better
Here is the code as copied directly from the sketch editor:
#include<dht.h> // Including library for dht
#include<LiquidCrystal.h>
LiquidCrystal lcd(7, 6, 5, 4, 3, 2);
#define dht_dpin 12
dht DHT;
#define pwm 9
byte degree[8] =
{
0b00011,
0b00011,
0b00000,
0b00000,
0b00000,
0b00000,
0b00000,
0b00000
};
void setup()
{
lcd.begin(16, 2);
lcd.createChar(1, degree);
lcd.clear();
lcd.print(" Fan Speed ");
lcd.setCursor(0,1);
lcd.print(" Controlling ");
delay(2000);
analogWrite(pwm, 255);
lcd.clear();
lcd.print("Circuit Digest ");
delay(2000);
}
void loop()
{
DHT.read11(dht_dpin);
int temp=DHT.temperature;
lcd.setCursor(0,0);
lcd.print("Temperature:");
lcd.print(temp); // Printing temperature on LCD
lcd.write(1);
lcd.print("C");
lcd.setCursor(0,1);
if(temp <26 )
{
analogWrite(9,0);
lcd.print("Fan OFF ");
delay(100);
}
else if(temp==26)
{
analogWrite(pwm, 51);
lcd.print("Fan Speed: 20% ");
delay(100);
}
else if(temp==27)
{
analogWrite(pwm, 102);
lcd.print("Fan Speed: 40% ");
delay(100);
}void setup() {
// put your setup code here, to run once:
}
Which results in the following error messages:
sketch_dec27a:6: error: 'dht' does not name a type
sketch_dec27a:6: error: 'dht' does not name a type
dht DHT;
^
C:\Users\wfene\OneDrive\Documents\Arduino\sketch_dec27a\sketch_dec27a.ino: In function 'void loop()':
sketch_dec27a:39: error: expected unqualified-id before '.' token
DHT.read11(dht_dpin);
^
sketch_dec27a:40: error: expected primary-expression before '.' token
int temp=DHT.temperature;
^
exit status 1
'dht' does not name a type
* If I could just get past the 'dht DHT; I'm sure the rest can be sorted out. I wonder if the 'copy > paste' I do causes the error but the code looks just like the listing on the project page. I have 5 of these DHT sensors and have ideas for all ! If I never get the code sorted for them they are useless !
Thanks in advance for your help.
After much surfing I concluded that the error was based on which 'dth lib ' one used ! One github repository actually bemoaned the fact that the syntax in the various dthlib s varied widely and because the sketch code [c++] is case sensitive beginners like me will chase errors because of this.
Bottom line I found one that had sample code syntax which I transposed to my project and got to compile !
Glad you got it working.. I compiled your program and it has no errors here. So no doubt the library was the culprit