One should download a library named TimerOne.h and should depose this library in the library folder of the sketckbook. But when looking through the software code of the downloaded EKG shield file, I can not see that his libray TimeOne.h is included in the .ino file. But I read the following comment:
// Timer2
// Timer2 is used to setup the analag channels sampling frequency and packet update.
// Whenever interrupt occures, the current read packet is sent to the PC
// In addition the CAL_SIG is generated as well, so Timer1 is not required in this case!
Is the TimerOne.h library not required?
Is this for the Arduno IDE example? Only FlexiTimer2 seems to be included and required.
This is the example from the IDE.
Did you install our Arduino package? To be able to select the example for SHIELD-EKG-EMG you might need to select temporarily one of our board OLIMEXINO-328 or OLIMEXINO-32u4.
Check this guide: https://www.olimex.com/Products/Duino/_resources/Arduino_instructions.pdf