From the data sheet: This interrupt can wake the device from Sleep. The user, in the=20 interrupt service routine, can clear the interrupt in the following manner: a) Any read or write of PORTB. This will end the mismatch condition. b) Clear flag bit RBIF. A mismatch condition will continue to set flag=20 bit RBIF. Reading PORTB will end the mismatch condition and allow flag bit RBIF to=20 be cleared. On 4/06/2015 10:07 PM, Murat Seven wrote: > Hi, > > Why RBIF not clearing? > --=20 ___________________________________________ David Duffy Audio Visual Devices P/L Unit 8, 10 Hook St, Capalaba 4157 Australia Ph: +61 7 38235717 Fax: +61 7 38234717 Our Web Site: www.audiovisualdevices.com.au ___________________________________________ --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .