| 摘要 |
To be able to transmit the data to be printed out by a number of printers at the one time, the central processing unit outputs addresses which are allocated to the printers selected for the printing; furthermore, it transmits the data to be printed to the printers via a common transmission line. Each printer exhibits an address field identifying it. When an address is received via the transmission line, the received address is compared with the printer's own address field in order to determine whether this printer is addressed by the central processing unit. If this is so, a latch is set which enables the printer control circuit for the data reception and the data printout to process the data transmitted by the central processing unit. When the latch is set, the printer waits for transmitted data. This latch remains set even when the central processing unit is addressing other printers for printing out data so that the printer already addressed continues to wait for the reception of data. If all selected printers are addressed, the central processing unit transmits data which are received and printed out simultaneously by each printer addressed.
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