Background: I need to assemble a solution which is to have a Microcontroller (uC), SD Card, GSM, GPS and Temperature sensor. Till now, I have coupled an Arduino Uno Shield with Adafruit GSM Shield (GSM + SD).
The program compares the real-time GPS coordinates with the reference coordinates on SD card and outputs red/ green LED output based on deviation (later, this is to be replaced by SMS option - to be sent based on any deviation). On compiling my program I see the following message (pls. note: for now, program is running fine - shows red/ green deviation LED output):
Sketch uses 24,038 bytes (74%) of program storage space. Maximum is 32,256 bytes. Global variables use 1,576 bytes (76%) of dynamic memory, leaving 472 bytes for local variables. Maximum is 2,048 bytes. Low memory available, stability problems may occur.
Question/ Request for Guidance: However, my concern is that going ahead I need to couple GSM (for SMS) and Analog sensor. Is it feasible - given the memory consumption above. If not, what precautions do I need to take to ensure that I can add GSM/ which GSM component should I choose.