AM79C978A AMD [Advanced Micro Devices], AM79C978A Datasheet - Page 102

• Manufacturer Part Number: AM79C978A
• Description: Single-Chip 1/10 Mbps PCI Home Networking Controller
• Manufacturer: AMD [Advanced Micro Devices]

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DATAPERR
STABORT
DEVSEL
FBTBC
RTABORT
Am79C978A
cleared by writing a 1. Writing a 0
has no effect. RTABORT is
cleared by H_RESET and is not
affected by S_RESET or by
setting the STOP bit.
STABORT is read only.
DEVSEL is read only.
During the data phase of all
memory read commands, the
Am79C978A controller checks
for parity error by sampling
AD[31:0], C/BE[3:0], and the
PAR lines. During the data phase
of all memory write commands,
the
checks the PERR input to detect
whether the target has reported a
parity error.
DATAPERR
Am79C978A
cleared by writing a 1. Writing a 0
has no effect. DATAPERR is
cleared by H_RESET and is not
affected by S_RESET or by
setting the STOP bit.
Send Target Abort. Read as ze-
ro; write operations have no ef-
fect. The Am79C978A controller
will never terminate a slave ac-
cess
sequence.
Device Select Timing. DEVSEL
is set to 01b (medium), which
means that the Am79C978A con-
troller will assert DEVSEL two
clock periods after FRAME is
asserted.
Data
DATAPERR is set when the
Am79C978A controller is the cur-
rent bus master and it detects a
data parity error and the Parity
Error Response enable bit (PCI
Command register, bit 6) is set.
Fast
Read as one; write operations
have no effect. The Am79C978A
Am79C978A
Back-To-Back
Parity
with
is
a
is
Error
controller
controller
set
target
set
Detected.
controller
Capable.
by
by
abort
Am79C978A
and
and
the
the
6-5
4
3-0
PCI Revision ID Register
Offset 08h
The PCI Revision ID register is an 8-bit register that
specifies the Am79C978A controller revision number.
The value of this register is 5Xh with the lower four bits
being silicon-revision dependent.
The PCI Revision ID register is located at offset 08h in
the PCI Configuration Space. It is read only.
PCI Programming Interface Register
Offset 09h
The PCI Programming Interface register is an 8-bit reg-
ister that identifies the programming interface of
Am79C978A controller. PCI does not define any specific
register-level programming interfaces for network de-
vices. The value of this register is 00h.
The PCI Programming Interface register is located at
offset 09h in the PCI Configuration Space. It is read only.
PCI Sub-Class Register
Offset 0Ah
The PCI Sub-Class register is an 8-bit register that iden-
tifies specifically the function of the Am79C978A con-
troller. The value of this register is 00h which identifies
the Am79C978A device as an Ethernet controller.
The PCI Sub-Class register is located at offset 0Ah in
the PCI Configuration Space. It is read only.
RES
NEW_CAP New Capabilities. This bit indi-
RES
controller is capable of accepting
fast back-to-back transactions
with the first transaction address-
ing a different target.
zero; write operations have no
effect.
cates whether this function imple-
ments
capabilities such as PCI power
management. When set, this bit
indicates the presence of New
Capabilities. A value of 0 means
that
implement New Capabilities.
have no effect. The Am79C978A
controller supports the Linked
Additional Capabilities List.
zero; write operations have no
effect.
Reserved locations. Read as
Read as one; write operations
Reserved locations. Read as
this
a
function
list
of
does
extended
not