| 摘要 |
PURPOSE:To enable data transfer covering the range from large amount of data to small amount of data without increasing the number of bits in a counter part by permitting data transmission instructing information to designate the number of transmission bytes or that of transmission blocks. CONSTITUTION:If a command is decoded by a decoder 7 and transmission by a block designation is instructed, the effective instruction by a multiplexer 9 through a NOT circuit 8 is given, and the contents of a transmission quantity instruction part 6 is set to a high order bit part in a register 4 through the multiplexer 9. If transmission by a byte designation is instructed, the effective instruction is given to a multiplexer 10, and the contents of the transmission quantity instruction part 6 is set to a low order part in the register 4 through the multiplexer 10. A data transmission control part 11 transfers data while decrementing the contents of the register 4. |
