Hi there, I did come across abt this IXP1200 mailing list thru websearch. As am new to this area, please do make me sense abt the usage of Interrupts on SA (Strong Arm) side from uEngine. Query : For interrupting a praticular thread in the uEngine from SA, am using INTER_THD_SIG register : *((unsigned int*) (0xB004 01C0))=thd_id // thd_id range : 0 to 23 Afore mentioned C statement would interrupt a thread in the uEngine based on thd_id. Where as in other case, Interrupting SA from uEgine, am not sure abt making use of IREG ... I would appreciate if some one make me sense in accomplishing the following required task. 1. Interrupting SA from uEngine (by IREG) 2. Capturing interrupt at SA which has been asserted by uEngine 3. Serving the Interrupt by making use of vector table, handler & etc... Sample snippet would be greatly appreciated for the afore mentioned request. Thanks & Kindest Regards Param