The 723646 is a 1K x 36 x 2 Triple Bus sync FIFO memory which supports clock frequencies up to 83 MHz and has read access times as fast as 8 ns. FIFO data can be read out and written using either 18-bit or 9-bit formats with a choice of Big- or Little-Endian configurations. The clocks for each port are independent of one another and can be asynchronous or coincident. Communication between each port may bypass the FIFOs via two mailbox registers. These devices can operate in the IDT Standard mode or First Word Fall Through mode.