AM79C978 Advanced Micro Devices, AM79C978 Datasheet - Page 173

• Manufacturer Part Number: AM79C978
• Description: Single-Chip 1/10 Mbps PCI Home Networking Controller
• Manufacturer: Advanced Micro Devices

9-8
7-0
BCR40: PCI DATA Register 3 (DATA3) Alias
Register
Note: This register is an alias of the DATA register and
also of the DATA_SCALE field of the PCMCR register.
Since these two are read only, BCR40 provides a
means of programming them through the EEPROM.
The contents of this register are copied into the corre-
sponding fields pointed with the DATA_SEL field set to
three. Bits 15-0 in this register are programmable
through the EEPROM.
Bit
15-10 RES
9-8
D2_SCALE These bits correspond to the
DATA2
Name
D3_SCALE These bits correspond to the
DATA_SCALE
PMCSR (offset Register 44 of the
PCI configuration space, bits 14-
13). Refer to the description of
DATA_SCALE for the meaning of
this field.
These bits are always read ac-
cessible. D2_SCALE is read only.
Cleared by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
These bits correspond to the PCI
DATA register (offset Register 47
of the PCI configuration space,
bits 7-0). Refer to the description
of DATA register for the meaning
of this field.
These bits are always read ac-
cessible. DATA2 is read only.
Cleared by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
Description
Reserved locations. Written as
zeros and read as undefined.
DATA_SCALE field of the PMC-
SR (offset Register 44 of the PCI
configuration space, bits 14-13).
Refer
DATA_SCALE for the meaning of
this field.
These bits are always read ac-
cessible. D3_SCALE is read only.
Cleared by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
to
the
field
description
of
the
Am79C978
of
7-0
BCR41: PCI DATA Register 4 (DATA4) Alias
Register
Note: This register is an alias of the DATA register and
also of the DATA_SCALE field of the PCMCR register.
Since these two are read only, BCR41 provides a
means of programming them through the EEPROM.
The contents of this register are copied into the corre-
sponding fields pointed with the DATA_SEL field set to
four. Bits 15-0 in this register are programmable
through the EEPROM.
Bit
15-10 RES
9-8
7-0
DATA3
Name
D4_SCALE These bits correspond to the
DATA4
These bits correspond to the PCI
DATA register (offset Register 47
of the PCI configuration space,
bits 7-0). Refer to the description
of DATA register for the meaning
of this field.
These bits are always read ac-
cessible. DATA3 is read only.
Cleared by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
Description
Reserved locations. Written as
zeros and read as undefined.
DATA_SCALE field of the PMC-
SR (offset register 44 of the PCI
configuration space, bits 14-13).
Refer
DATA_SCALE for the meaning of
this field.
Read
D4_SCALE is read only. Cleared
by H_RESET and is not affected
by S_RESET or setting the STOP
bit
These bits correspond to the PCI
DATA register (offset Register 47
of the PCI configuration space,
bits 7-0). Refer to the description
of DATA register for the meaning
of this field.
Read accessible always. DATA4
is
H_RESET and is not affected by
S_RESET or setting the STOP
bit.
read
to
accessible
only.
the
description
Cleared
always.
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of