This standard defines a signaling method for asynchronous, fully interlocked, bidirectional parallel communications between hosts and printers or other peripherals. A functional subset of the signaling method may be implemented on personal computers (PCs) or equivalent parallel port hardware with new software. This standard recommends new electrical interfaces, cabling, and interface hardware that provides improved performance while retaining backward compatibility with this subset. This standard also specifies a format for a peripheral identification string and a method of returning this string to the host outside of the bidirectional data stream.