Fujitsu MB96300 series Hardware Manual page 302

CHAPTER 12 EXTERNAL BUS INTERFACE
12.1.2 Terminology
This chapter explains some basic terms of the External Bus Interface.
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Bus mode
Bus mode means the mode for controlling the internal ROM operation and external access function. The bus
mode depends on the EAE[5:0] and ERE bits of the External Bus Mode register (EBM).
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Access mode
Access mode means the mode for controlling the external bus format.
The data width of the external bus is specified by the BW-bit of the External Area Configuration registers
(EACL[5:0]).
If supported by the device, it is possible to select between address/data multiplex and address/data non-
multiplex by setting the NMS bit of the External Bus Mode register. This setting is valid for all external
areas.
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External Boot Vector
Devices with an external bus interface offer the possibility to fetch the Boot Vector (User program start
address) and a mode byte from an external memory instead of using the internal data (Internal Vector mode).
The mode byte which is read together with the Boot Vector is copied to the External Bus Mode register
(EBM) and overwrites the initial setting.
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MB96300 Super Series Hardware Manual