Hello! Im Berkay, studying Electronic Engineering.I am working on a project but i am new with arduino and i have a problem with codes. I need to read ecg signal from sd card and send out to pwm output port by mega2560. how can i read an ecg signal from sd card? or can i create an ecg signal in arduino by coding? i am really confused and i dont know what to do. PLEASE, HELP ME! 
There was another person on the forum doing the same thing, within the last week.
Search to see what was mentioned in that thread.