| 摘要 |
<p>PURPOSE:To simplify a system by adding a signal transfer path for attaining an access to an expanding memory from a host processor. CONSTITUTION:The signal transfer path SL is disposed at the input and output part of a special processor DSP directly execute the memory access to the expanding memory EXRAM from the host processor CPU. This signal transfer path SL is not especially limited and disposed in an interface circuit INF. Namely, the signal transfer path SL, as shown by dotted lines selectively transfers a signal of low order or high order 8 bits to data terminals D0-D7 to the expanding memory EXRAM of terminals IO0-IO15 for transferring data between the host processor CPU and the special processor DSP. Thereby, since the expanding memory EXRAM can be made access via the special processor DSP from the host processor CPU, the system can be simplified and a high speed access can be attained.</p> |
