| 摘要 |
PURPOSE:To enable a central processor to process an input/output data in the form of a fixed length data in a system using a variable length code, by putting an invalid code into an idle region. CONSTITUTION:A data process system comprises with a mutual connection among an input device 1, a central processor 2 and an output device 3 via data buses 4 and 5. The variable length character code is transferred by a byte in the device 1 to a buffer register 7 from a data buffer 6 via a counter circuit 9. In this case, the circuit 9 counts the number of bytes of the character code to be transferred to the register 7 and then report the end of transfer to a data control circuit 10. Receiving this report, the circuit 10 puts an invalid code into the rest part of the register 7 and then transmits it to the processor 2 in the form of a fixed length daga. The device 2 eliminates the invalid code for delivery of an output through an output deciding circuit 12. |
