terryking228:
Check for alternatives to other interfaces and LIST all the pins they need...
let me try... im very new to arduino...
--LCD needs 7 digitan pins
--Keypad needs 7 digital pins
--2 Fans (no speed control , only on/off , will work together) needs 1 digital pin
--3 input pins (CO2 sensor, temperature, water) needs 3 analog pins , 1 each
--LED , i will have 3 groups , 15 + 15 + 10 , i will light each group separately , needs 3 digital pins , 1 each group
--GSM shield needs....i have no idea...
So to sum up , i need 7+7+1+3+3 = 21 pins... At least...
18 Digital and 3 Analog...
Arduino uno has 14 Digital I/O , so it's not good for me....
Arduino mega 2560 has 54 Digital I/O , so its good for me !
Is this correct ?