8.6 Status/Control Registers

Although these registers are not specifically part of the interrupt control hardware, two of the CPU Control registers contain bits that control interrupt functionality. For more information on these registers, refer to “Enhanced CPU” (www.microchip.com/DS70005158) in the “dsPIC33/PIC24 Family Reference Manual”.

• The CPU STATUS Register, SR, contains the IPL[2:0] bits (SR[7:5]). These bits indicate the current CPU Interrupt Priority Level. The user software can change the current CPU Interrupt Priority Level by writing to the IPLx bits.
• The CORCON register contains the IPL3 bit, which together with IPL[2:0], also indicates the current CPU priority level. IPL3 is a read-only bit so that trap events cannot be masked by the user software.