I just ordered an Arduino Mega 2560, and so far, I've managed to upload programs to it successfully. However, whenever I tried using any of the extra digital pins that it comes with, they wouldn't work. I just tried using them again—specifically, here is the code I wrote before the void setup() part of my program:
int cathode01 = 22;
int cathode02 = 23;
int cathode03 = 24;
int cathode04 = 25;
int cathode05 = 26;
Then, when I tried uploading the program, I kept getting a message that said "avrdude: stk500_2_ReceiveMessage(): timeout." Now whenever I try uploading anything at all to the Mega, I receive the exact same message. I've tried holding down the reset button before uploading programs, I've tried removing the Mega from "Networks" under "System Preferences," I've tried checking the board and the serial port…but to no avail. Please help? Thanks.