The HD-6408 is a CMOS/LSI Manchester Encoder/Decoder
for creating a very high speed asynchronous serial data bus.
The Encoder converts serial NRZ data (typically from a shift
register) to Manchester II encoded data, adding a sync pulse
and parity bit. The Decoder recognizes this sync pulse and
identifies it as a Command Sync or a Data Sync. The data is
then decoded and shifted out in NRZ code (typically into a
shift register). Finally, the parity bit is checked. If there were
no Manchester or parity errors the Decoder responds with a
valid word signal. The Decoder puts the Manchester code to
full use to provide clock recovery and excellent noise
immunity at these very high speeds.
The HD-6408 can be used in many commercial applications
such as security systems, environmental control systems,
serial data links and many others. It utilizes a single 12 x
clock and achieves data rates of up to one million bits per
second with a very minimum overhead of only 4 bits out of
20, leaving 16 bits for data.