Artesyn BajaPPC-750, Руководство пользователя

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6-8 BajaPPC-750: VMEbus Interface
May 2002
6.2.2 PCI Base Address Register
The Universe PCI Configuration Base Address Register, PCI_BS, at hex offset 010
16
defines the base address of the Universe register space on PCI and has a resolution
of 4 kilobytes. In addition, it determines whether the Universe registers are
mapped to memory or I/O space. If mapped to memory space, the registers may
be located anywhere in the address space, but they should not be pre-fetched.
For added flexibility, a second Universe PCI Configuration Base Address Register,
PCI_BS1, exists at hex offset 014
16
with identical bit assignments. The SPACE bit
assignment for this register is the logical inversion of the SPACE bit for PCI_BS.
6.2.3 PCI Configuration Space and Status Register
The Universe PCI Configuration Space Control and Status Register, PCI_CSR, at
hex offset 004
16
defines the PCI space, parity handling characteristics, and other
general parameters. The BM bit allows the Universe to master the PCI bus. The
MS and IOS bits map the PCI space to memory or input/output space, respec-
tively. For additional information about PCI, please refer to the
PCI Local Bus
Specification .
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
BS
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
BS 0 0 0 0 0 0 0 0 0 0 0
SPACE
Register Map 6-1. Universe PCI Base Address, PCI_BS
BS Base address.
SPACE Local bus address space. (read only)
Binary 0=memory, 1=I/O