Motorola MVME2300 Series 사용자 설명서

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Functional Description
http://www.motorola.com/computer/literature
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The PCI interface may operate at any clock speed up to 33MHz. The 
PCLK input must be externally synchronized with the MCLK input, and 
the frequency of the PCLK input must be exactly half the frequency of the 
MCLK input.
PCI Address Mapping
The Raven ASIC provides three resources to PCI:
Configuration registers mapped into PCI Configuration space
MPC bus address space mapped into PCI Memory space
RavenMPIC control registers mapped into either PCI I/O space or 
PCI Memory space
Configuration Registers
The Raven has no IDSEL pin. Instead, an internal connection made within 
the Raven logically associates the assertion of IDSEL with the assertion of 
AD31.
Raven provides a configuration space that is fully compliant with the PCI 
Local Bus Specification 2.0 definition for configuration space. Two base 
registers within the standard 64-byte header are used to control the 
mapping of RavenMPIC. One register is dedicated to mapping 
RavenMPIC into PCI I/O space; the other register is dedicated to mapping 
RavenMPIC into PCI Memory space. The mapping of MPC address space 
is handled by device-specific registers located above the 64-byte header. 
These control registers support a mapping scheme that is functionally 
similar to the PCI-to-MPC mapping scheme described in the section on 
 earlier in this chapter.