| 摘要 |
PURPOSE:To attain an emulation memory access at a high speed by securing the working of an emulation memory circuit with a mapper circuit removed. CONSTITUTION:In a single chip mode SCM, a control signal is equal to '0' and a selector 14 selects A16-A8 out of the address input of a macroprocessor MP 11 as a higher rank address IA-IA8 of an emulation memory EM 15. An address space of the MP 11 has 64K bytes in the SCM and therefore the most significant bit IA16 in an address given to a higher rank address of the EM 15 is always fixed at the specific value. Therefore the access to be applied to the EM 15 in the SCM is directly given to an address shown by the address output A15-IA0 of the MP 11. Thus the copy of an internal memory of the MP 11 is maintained at lower 64K bytes of the EM 15. Then it is possible to know the read/write address/data applied to the internal memory of the MP 11. |
