PURPOSE: To simply control of an extension unit interface and reduce its load by sending command to a specific extension unit in place of sending command to each extension unit.
CONSTITUTION: A control block 7 of a cassette feeder 3 monitors an address bus 16 and discriminates to be communication to the feeder 3 itself when data of the bus 16 indicate an address 2, monitors an RW signal line and executes data reception or transmission processing. Furthermore, the block 7 executes no processing and terminates its processing when the data of the bus 16 indicate '1'. The block 7 discriminates it to be data transmission to a cassette feeder 4 when data of the bus 16 indicate '3' and the RW signal line is at an L level to analyze command data to the feeder 4 and to drives a carrier roller 13 when the data indicate a paper feed command. Thus, the content from the main body to other cassette feeder is analyzed and the operation required for the other cassette feeder is executed without a command to the main body.
HORI KENJIRO
KURAMOCHI YOSHIMI
KISHIDA TETSUO
OTAKA KOICHI
TAKUBO TAKESHI
