Motorola MVME162 Manual De Usuario

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Functional Description
MVME162IG/D2
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Data Bus Structure
The local data bus on the MVME162 is a 32-bit synchronous bus that is based 
on the MC68040 bus, and which supports burst transfers and snooping. The 
various local bus master and slave devices use the local bus to communicate. 
The local bus is arbitrated by priority type arbiter and the priority of the local 
bus masters from highest to lowest is: 82596CA LAN, 53C710 SCSI, VMEbus, 
and MPU. Generally speaking, any master can access any slave; however, not 
all combinations pass the common sense test. Refer to the MVME162 Embedded 
Controller Programmer’s Reference Guide
 and to the user’s guide for each device 
to determine its port size, data bus connection, and any restrictions that apply 
when accessing the device.
MC68040 or MC68LC040 MPU
The MC68040 or MC68LC040 processor is used on the MVME162. The 
MC68040 has on-chip instruction and data caches and a floating point 
processor. The major difference between the two processors is that the 
MC68040 has a floating point coprocessor. Refer to the M68040 Microprocessor 
User’s Manual
 for more information.
MC68xx040 Cache
The MVME162 local bus masters (VMEchip2, MC68xx040, 53C710 SCSI 
controller, and 82596CA Ethernet controller) have programmable control of 
the snoop/caching mode. The MVME162 local bus slaves which support 
MC68xx040 bus snooping are defined in the Local Bus Memory Map table later 
in this chapter.
No-VMEbus-Interface Option
The MVME162 can be operated as an embedded controller without the 
VMEbus interface. To support this feature, certain logic in the VMEchip2 has 
been duplicated in the MCchip. This logic is inhibited in the MCchip if the 
VMEchip2 is present. The enables for these functions are controlled by 
software and MCchip hardware initialization.
Contact your local Motorola sales office for ordering information.