| 摘要 |
PURPOSE:To easily attain more high-speed data conversion as compared to a method for executing an ordinary CPU and an ordinary program by comparing data strings while executing DMA data transfer, and converting the data into codes at real time. CONSTITUTION:A signal generator 1 sends a data reading signal READ to an input/output device and outputs data to a data bus line. At that time, the generator 1 sends a data writing signal WRITE to a main memory and the data is written in an address specified by a counter 4. A value '1' is subtracted from the contents of a counter 3 by the signal READ and a value '1' is added to the contents of a counter 4 by the signal WRITE to prepare data transfer. Simultaneously, these data are compared with a registered data string by a data string detector 6, and when both the data do not coincide with each other, the succeeding data transfer is started. At the time of coincidence, a coincidence signal, a code and length are outputted from the detector 6. A subtractor 5 subtracts the length of the data string from the output of the counter 4 and sets up the subtracted value in the counter 4. |
