| 摘要 |
PURPOSE:To attain miniaturization of the titled device, simplicity of the software and high speed data transmission by adopting a double buffer for a transmission data memory. CONSTITUTION:A transmission data memory 32 is accessed from both a CPU12 and a data transmission section 11 by using a multiplexer 32 to switch an address signal. Further, the transmission data memory 32 is placed at a part of a memory address space of the CPU12 so that it can read/write directly a signal through a two-way buffer 33. While a buffer pointer of the transmission data memory 32 used as a double buffer is inverted at each establishment of a condition, one is used for transmission and the other is used for data operation and writing in parallel. |
