[NMIEN] enable/disable non maskable interrupts (NMI's)

[SETVBV] sets an interrupt vector or system timer vector

[XITVBV] exit the vertical blank interrupt routine 

[SYSVBV] vertical blank interrupt routine entry point

[VVBLKI] vector to the immediate vertical blank interrupt routine

[VVBLKD] vector to the deferred vertical blank interrupt routine

[SYSVBL] the vertical blank interrupt routine


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see [Interrupts], [Topic list]