Initializing The Vme Interface; Vme Pci Configuration Registers; Local Bus A1,0 And Siz1,0 To Pci Be# Translation - DEC Digital Alpha VME 4/224 User Manual

Table 10–14 Local Bus A1,0 and SIZ1,0 to PCI BE# Translation
Local Bus
A1,0 SIZ1,0 Data
00 00 D[31:0]
00 11 D[31:8]
01 11 D[23:0]
00 10 D[15:0] L
01 10 D[23:8]
10 10 D[15:0]
00 01 D[15:8] L
01 01 D[7:0] L
10 01 D[15:8]
11 01 D[7:0]

10.5 Initializing the VME Interface

The Digital Alpha VME 4 firmware must set up some registers in the VME
interface as fixed configuration values. This section describes these registers and
other VME interface initialization.
The firmware uses the following procedure to set up the VME interface for use
with the default values for the DC7407 registers:
1. Set up the three PCI base registers in the VME interface.
2. Program scatter-gather RAM as needed.
3. Configure the VIC64 for initialization. Some timing control register values
are defined.
4. Operate the VME interface.
10.5.1 VME PCI Configuration Registers
CPU Address: 0x1E0000000 - 0x1E0001FE0
PCI Configuration: 0x00000800 - 0x000008FF
The PCI bus interface to VMEbus must be configured at startup by writing three
base address registers within the DC7407. A fourth register can be used to read
the hardware setting for the second VME window if required. These registers are
accessible only through PCI configuration address space. Once these registers are
initialized, PCI memory space can be used to set up the remainder of the VME
subsystem for access to VME devices.
10–30 VME Interface
Mode 0 Mode 1 Mode 2
BE# BE# BE#
0000 0000 0000
1000 0100 0010
0001 0010 0100
1100 1100 0011
1001 0110 0110
0011 0011 1100
1110 1101 1011
1101 1110 0111
1011 0111 1110
0111 1011 1101
Mode 3
BE#
0000
0001
1000
0011
1001
1100
0111
1011
1101
1110