HP 64780A, Руководство пользователя

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Concepts of the EMSIM and EMRAM
The 68360 processor provides an array of on-chip peripherals which are configured
and used via memory mapped registers. These registers directly control many
aspects of the external operation of the processor. The most notable of these
on-chip peripherals is the SIM (System Integration Module). For example, address
bits A28 through A31 can be configured as either address bits or byte write-enable
signals. Selection of these alternative uses drastically changes the external
behavior of the processor. Internal to the processor, the full 32-bit address and bus
control signals are always maintained. What is seen external to the processor is
determined by the current contents of the SIM register set.
The 68360 processor also has internal, on-board, static RAM which can be
configured to be addressable anywhere within the address range. The processor
RAM register set is used to enable this on-board RAM and to define where it is
currently positioned in the 32-bit address space.
The emulator needs access to the full 32-bit address, function codes, and other
control signals for proper operation of the emulation-bus analyzer and the
emulation memory system. To provide this access when these signals are not
available external to the processor, an external bus decoder is designed into the
emulator; it recreates these signals.
The following is a view of the emulator implementation:
Chapter 13: Concepts of the EMSIM and EMRAM
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