User’s Manual U14272EJ3V0UM
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CHAPTER 6 BUS CONTROL
6.1 MBA Host Bridge
The MBA (Modular Bus Architecture) Host Bridge is an interface between the CPU core and the MBA bus and
operates as an external agent to the CPU core. It handles all requests from the CPU core if it is provided proper
resources. The MBA Host Bridge can decode the entire physical address space to start appropriate bus accesses
such as MBA requests, MBA - ISA protocols, or external ROM accesses through the peripheral bus. It also has
functions as a host bridge to implement proper cycle timings and bus transaction protocols.
Figure 6-1. V
R
4181 Internal Bus Structure
MBA Bus
ISA Bridge
Internal ISA
Peripherals
MBA Peripherals
(LCD, DMA)
Memoty
Controller
V
R
4110
CPU Core
MBA
Host Bridge
Internal ISA Bus
SysAD Bus