参数资料
型号: S5933QE
厂商: APPLIEDMICRO INC
元件分类: 总线控制器
英文描述: PCI BUS CONTROLLER, PQFP160
封装: PLASTIC, QFP-160
文件页数: 107/176页
文件大小: 823K
代理商: S5933QE
3-44
S5933
PCI CONFIGURATION REGISTERS
EXPANSION ROM BASE ADDRESS
REGISTER (XROM)
Register Name:
Expansion ROM Base Address
Address Offset:
30h
Power-up value:
00000000h
Boot-load:
External nvRAM offset
70h
Attribute:
bits 31:11, bit 0 Read/Write; bits
10:1 Read Only
Size:
32 bits
31
0
1
10
Bit
Value
Address Decode
Enable (RW)
0=Disabled
1=Enabled
Reserved (RO)
Programmable (R/W)
11
Figure 12. Expansion ROM Base Address Register
The expansion base address ROM register provides
a mechanism for assigning a space within physical
memory for an expansion ROM. Access from the PCI
bus to the memory space defined by this register will
cause one or more accesses to the S5933 control-
lers’ external BIOS ROM (or nvRAM) interface. Since
PCI bus accesses to the ROM may be 32 bits wide,
repeated operations to the ROM are generated by
the S5933 and the wider data is assembled internal
to the S5933 controller and then transferred to the
PCI bus by the S5933.
Table 25. Expansion ROM Base Address Register
Bit
Description
31:11
Expansion ROM Base Address Location. These bits are used to position the decoded region in
memory space. Only bits which return a 1 after being written as 1 are usable for this purpose. These
bits are individually enabled by the contents sourced from the external boot memory (EPROM or
nvRAM). The desired size for the ROM memory is determined by writing all ones to this register and
then reading back the contents. The number of bits returned as zeros, in order from least significant
to most significant bit, indicates the size of the expansion ROM. This controller limits the expansion
ROM area to 64K bytes. The allowable returned values after all ones are written to this register are
shown in Table 26.
10:1
Reserved. All zeros.
0
Address Decode Enable. The Expansion ROM address decoder is enabled or disabled with this bit.
When this bit is set, the decoder is enabled; when this bit is zero, the decoder is disabled. It is required
that the PCI command register also have the memory decode enabled for this bit to have an effect.
相关PDF资料
PDF描述
S6A0032 16 X 80 DOTS DOT MAT LCD DRVR AND DSPL CTLR, UUC138
S6A0069 16 X 40 DOTS DOT MAT LCD DRVR AND DSPL CTLR, UUC80
S6A0078 34 X 120 DOTS DOT MAT LCD DRVR AND DSPL CTLR, UUC183
S80296SA40 16-BIT, 40 MHz, MICROCONTROLLER, PQFP100
S80486-DX4-75-S-V-8-B 32-BIT, 75 MHz, MICROPROCESSOR, PQFP208
相关代理商/技术参数
参数描述
S5935 制造商:AMCC 制造商全称:Applied Micro Circuits Corporation 功能描述:PCI Product
S5935_07 制造商:AMCC 制造商全称:Applied Micro Circuits Corporation 功能描述:PCI Product
S59355QRC 制造商:AppliedMicro 功能描述:
S5935QF 制造商:AMCC 制造商全称:Applied Micro Circuits Corporation 功能描述:PCI Product
S5935QRC 制造商:AppliedMicro 功能描述:PCI Master Device 160-Pin PQFP