http://arduino.cc/en/uploads/Main/ArduinoUno_R3_Front.jpg The above is a link to the pins for the R3 for convenience. I bought a TFTLCD Touchscreen shield from Adafruit. The problem is it takes up all the pins except the two on the top and bottom on the left side as shown in the link above.
My plan is to have the arduino send a High/Low signal to another microcontroller (A Pic microcontroller) and I need to power the arduino using something like a 9V battery. The problem is these pins are already taken by the touchscreen shield.
What do you guys recommend? I want to try avoid buying anything extra for this purpose as that would take time to ship.