this is the compiler error message
sketch_may05a.ino: In function 'void setup()':
sketch_may05a:3: error: 'cli' was not declared in this scope
sketch_may05a:4: error: 'TCCR1A' was not declared in this scope
sketch_may05a:5: error: 'TCCR1B' was not declared in this scope
sketch_may05a:6: error: 'TCNT' was not declared in this scope
sketch_may05a:7: error: 'OCR1A' was not declared in this scope
sketch_may05a:8: error: 'WGM12' was not declared in this scope
sketch_may05a:9: error: 'CS12' was not declared in this scope
sketch_may05a:9: error: 'CS0' was not declared in this scope
sketch_may05a:10: error: 'TIMSK1' was not declared in this scope
sketch_may05a:10: error: 'OCIEA' was not declared in this scope
sketch_may05a:11: error: 'sei' was not declared in this scope