The Digital Blocks DB8259S Programmable Interrupt Controller IP core is a full function equivalent to the Intel Intel 8259A / Intersil 82C59A / NEC uPD8259A devices, with the update to a synchronous design.
The DB8259S RTL Verilog / VHDL outputs were compared to the Intel 8259A device on a cycle-by-cycle basis as captured & represented by the Digital Blocks testbench suite.
The DB8259S Interrupt Controller manages up to eight vectored priority interrupts for a microprocessor. Using multiple instantiations of the DB8259S core and programming it to cascade mode enables up to sixty-four vectored priority interrupts. More than sixty-four vectored interrupts can be accomplished by programming the DB8259S core to Poll Command Mode. Interrupt sources may be either edge or level triggered.