May u know how to stabilize the lcd display reading???
im using 16 x 2 lcd and pic18f4520....
im using thermocouple type K and ad595 to measurement temperature....but my temperature reading keep fluctuating +- 4 degree so much....
any idea can i to stabilize the reading??
hope anyone here can help me.....appreciated it much~
Average out the readings. A thermocouple probably isn't changing temperature all that fast anyway. Just read it 10 or 20 or whatever number of times is appropriate, storing the results as a running total. Then divide by the number of readings. Then display.
Someone else will probably post something more elegant, but that's my first thought.
EDIT: If you're programming in asm then you'd want to keep the number of readings to something like 8, 16, 32, 64 or whatever so you can divide by just shifting, rather than writing "difficult" division code.
hi,
One method is to use an analog technique of Differential control, using a digital approach within the PIC's program.
eg, take your '0 to 100Cdeg' jump as an example.
Compare the 'current latest' adc reading and compare it with the 'previous' stored value, if the absolute difference is greater than say 10% then use less samples in the averaging loop.
As the readings approach the final value start to increase the number of samples in the averaging.
hi,
One method is to use an analog technique of Differential control, using a digital approach within the PIC's program.
eg, take your '0 to 100Cdeg' jump as an example.
Compare the 'current latest' adc reading and compare it with the 'previous' stored value, if the absolute difference is greater than say 10% then use less samples in the averaging loop.
As the readings approach the final value start to increase the number of samples in the averaging.
hi,
One method is to use an analog technique of Differential control, using a digital approach within the PIC's program.
eg, take your '0 to 100Cdeg' jump as an example.
Compare the 'current latest' adc reading and compare it with the 'previous' stored value, if the absolute difference is greater than say 10% then use less samples in the averaging loop.
As the readings approach the final value start to increase the number of samples in the averaging.
hi futz,
The method works for me, I don't know the language the OP is using.??
If he wants to get a closer approximation to the D in PID, then he could use window values, say the number of windows equal to his maximum samples in an averaged number
Andy Lindsay (Parallax) wrote an awesome intro to PID. **broken link removed**. Easiest to understand intro I ever read. You can use the Stamp BASIC source as pseudo code.