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BD82HM55-SLGZS Datasheet, PDF (857/956 Pages) Intel Corporation – Intel® 5 Series Chipset and Intel® 3400 Series Chipset | |||
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Serial Peripheral Interface (SPI)
21.4.15
PREOPâPrefix Opcode Configuration Register
(GbE LAN Memory Mapped Configuration Registers)
Memory Address: MBARB + 94h
Default Value:
0000h
Attribute:
Size:
R/W
16 bits
Bit
15:8
7:0
Description
Prefix Opcode 1âR/W. Software programs an SPI opcode into this field that is
permitted to run as the first command in an atomic cycle sequence.
Prefix Opcode 0âR/W. Software programs an SPI opcode into this field that is
permitted to run as the first command in an atomic cycle sequence.
NOTE: This register is not writable when the SPI Configuration Lock-Down bit (MBARB + 00h:15)
is set.
21.4.16 OPTYPEâOpcode Type Configuration Register
(GbE LAN Memory Mapped Configuration Registers)
Memory Address: MBARB + 96h
Default Value:
0000h
Attribute:
Size:
R/W
16 bits
Entries in this register correspond to the entries in the Opcode Menu Configuration
register.
Note:
The definition below only provides write protection for opcodes that have addresses
associated with them. Therefore, any erase or write opcodes that do not use an address
should be avoided (for example, âChip Eraseâ and âAuto-Address Increment Byte
Programâ).
Bit
Description
15:14 Opcode Type 7âR/W. See the description for bits 1:0
13:12 Opcode Type 6âR/W. See the description for bits 1:0
11:10 Opcode Type 5âR/W. See the description for bits 1:0
9:8 Opcode Type 4âR/W. See the description for bits 1:0
7:6 Opcode Type 3âR/W. See the description for bits 1:0
5:4 Opcode Type 2âR/W. See the description for bits 1:0
3:2 Opcode Type 1âR/W. See the description for bits 1:0
Opcode Type 0âR/W. This field specifies information about the corresponding Opcode
0. This information allows the hardware to 1) know whether to use the address field
and 2) provide BIOS and Shared Flash protection capabilities. The encoding of the two
bits is:
1:0 00 = No address associated with this Opcode; Read cycle type
01 = No address associated with this Opcode; Write cycle type
10 = Address required; Read cycle type
11 = Address required; Write cycle type
NOTE: This register is not writable when the SPI Configuration Lock-Down bit (MBARB + 00h:15)
is set.
Datasheet
857
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