please help me .. i am using EFcom GSM-GPRS Arduino Shield,in data sheet they says it is fully compatible with arduino uno and as pin definition says analog input should be in ADC and as shown in the photo i can not put any wire in ADC because no pin in this place in arduino under it what should i do to connect analog sensor??!!!! can not uploud photo .. Adc is number 20 and arduino une have only 12 pins
What do you mean by
Adc is number 20
My Arduino Unos have more than 24 pins, including ADC 0 through 5. What do you really have and what are you really trying to do?
Why does GSM and/or GPRS need an analog input anyway? Temperature?
How'd you get more than 20 IO on an Uno? D0 to D13, A0 to A5 (D14 to D19). That's pretty much the limit unless you have a SMD '328P, in which case you may have A6 & A7 available, also (but not D20, D21).
I am away from my Unos right now, but those other pins might be 5 volts, 3.3 volts, ground, etc. I don't think that I said I/O.
24 is not enough then.
6 on power header
6 on analog header
8 on digital header
10 on other digital header (6 digital, SCL & SDA again, Gnd, Aref)
30 pins.
Maybe you were thinking 24 without the power header?
vaj4088 wrote (in part):
My Arduino Unos have more than 24 pins
and 30 is more than 24.
My Arduino Unos have D0 through D13, A0 through A5, Gnd, ARef, Vin, Gnd, Gnd, 5V, 3.3V, Reset, IORef, and 3 unmarked pins that may or may not be connected.
Some of these pins have multiple uses, such as A5 also being SCL.
That is either 29 or 32 pins.
29 pins and 32 pins are also more than 24 pins.
...and that is just the female headers. There are additional pins available at male headers.
The OP still has not answered the questions that I posed in reply #1.