Using the PIC18 rtosdemo1 (latest versions of everything), and changing just the processor & linker to 18f66j11 has a stack underflow error, from mplab sim: CORE-E0002: Stack under flow error occurred from instruction at 0x002d00 This stack underflow occurs in the portRESTORE_CONTEXT(); macro, inside the xPortStartScheduler() function in port.c I’ve used FreeRTOS on numerous different PIC18’s including the 87j ethernet series and never had any issues. This one seems specific to the 18f66j11 processor. Can someone help me track this down? Its killing me and my brain! -Todd

Ok, not a common issue I suppose. Could someone at least take a few minutes to try and replicate this on their setup so I know its not an isolated issue? Thanks, Todd