An integrated circuit memory device comprises a memory array to store
data, a circuit to output the data at a pin, and a register to store a
value that indicates a mode of operation of the integrated circuit memory
device. The mode of operation is selected from at least one of a
synchronous mode of operation and an asynchronous mode of operation.
During the synchronous mode of operation, the circuit outputs the data in
response to a transition of an external clock signal. During the
asynchronous mode of operation, the circuit outputs the data after a
period of time from when a transition of an external control signal is
detected.