The data processing system includes I/O units for transmitting and
receiving data, control units for processing the data, and a common bus
unit including a common bus. Function cards in each unit are daisy-chained
to I/O buses having characteristics to support hot-swapping, and both ends
of the I/O buses are terminated with resistors respectively. The units are
daisy-chained to the common bus, and both ends of the common bus are
terminated with resistors respectively. Drivers/receivers drive each bus
to transmit and receive data between the common bus and the I/O buses.
