Compaq 4000N - Manual (Page 42)

Chapter 3 Processor/Memory Subsystem
Compaq Deskpro 4000N and 4000S Personal Computers
First Edition - September 1997
3-8
3.2.5 SUBSYSTEM CONFIGURATION
The VT82C595 component provides the configuration function for the processor/memory
subsystem. Table 3-6 lists the configuration registers used for setting and checking such
parameters as cache (L2) control, system memory control, and PCI bus operation. These registers
reside in the PCI Configuration Space and accessed using the methods described in Chapter 4,
section 4.2.
Table 3–6. Host/PCI Bridge Configuration Registers (VT82C595)
Table 3-6.
Host/PCI Bridge Configuration Registers (VT82C595)
PCI Config.
Addr.
Register
Reset
Value PCI Config.
Addr.
Register
Reset
Value
00, 01h Vender ID 1106h 64h DRAM Timing ABh
02, 03h Device ID 0595h 65h DRAM Control Reg. 1 00h
04, 05h Command 0007h 66h DRAM Control Reg. 2 00h
06, 07h Status 67h DRAM Width 00h
08h Revision ID 68h UMA Control Reg. 1 00h
09-0Bh Class Code 69h UMA Control Reg. 2 00h
0Dh Latency Timer 00h 6Ah Refresh Control 00h
0Eh Header Type 00h 6Bh Misc. Cointrol 00h
0Fh BIST (read only) 6Ch SDRAM Control
50h Cache Control Reg. 1 00h 6Dh DRAM Control Drive Strength
51h Cache Control Reg. 2 00h 6Eh ECC Control Reg.
52h Non-Cacheable Control 02h 6Fh ECC Status Reg.
53h Misc. Control 00h 70h PCI Buffer Control 00h
54, 55h Non-Cacheable Area 1 00h 71h CPU-to-PCI Flow Cntl. Reg. 1 00h
56, 57h Non-Cacheable Area 2 00h 72h CPU-to-PCI Flow Cntl. Reg. 2 00h
58h DRAM Configuration 40h 73h PCI Master Control Reg.1 00h
59h DRAM Configuration 05h 74h PCI Master Control Reg. 2 00h
5A..5Fh DRAM ROW End Addr. 01h 75h PCI Arbitration 00h
60h DRAM Type 00h 76h Extension (PCI Arbitration) 00h
61..63h Shadow RAM Control 00h -- -- --
NOTE:
Refer to VIA Technologies, Inc. documentation for detailed description of registers.
Assume unmarked locations/gaps as reserved.