AM79C978A AMD [Advanced Micro Devices], AM79C978A Datasheet - Page 129

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

CSR39: Next Next Transmit Descriptor Address
Upper
Bit
31-16
15-0
CSR40: Current Receive Byte Count
Bit
31-16
15-12
11-0
CSR41: Current Receive Status
Bit
31-16
15-0
Name
RES
NNXDAU
Name
RES
RES
CRBC
Name
RES
CRST
These bits are read/write acces-
sible only when either the STOP
or the SPND bit is set. These bits
are unaffected by H_RESET,
S_RESET, or STOP.
These bits are read/write acces-
sible only when either the STOP
or the SPND bit is set. These bits
are unaffected by H_RESET,
S_RESET, or STOP.
These bits are read/write acces-
sible only when either the STOP
or the SPND bit is set. These bits
are unaffected by H_RESET,
S_RESET, or STOP.
Description
Reserved locations. Written as
zeros and read as undefined.
Contains the upper 16 bits of
the next next transmit descriptor
address pointer.
Description
Reserved locations. Written as
zeros and read as undefined.
Reserved locations. Read and
written as zeros.
Current Receive Byte Count.
This field is a copy of the BCNT
field of RMD1 of the current re-
ceive descriptor.
Description
Reserved locations. Written as
zeros and read as undefined.
Current Receive Status. This
field is a copy of bits 31-16 of
RMD1 of the current receive
descriptor.
Am79C978A
CSR42: Current Transmit Byte Count
Bit
31-16 RES
15-12 RES
11-0
CSR43: Current Transmit Status
Bit
31-16 RES
15-0
CSR44: Next Receive Byte Count
Bit
31-16 RES
15-12 RES
11-0
CXST
NRBC
Name
CXBC
Name
Name
Reserved locations. Written as
Reserved locations. Written as
Next Receive Byte Count. This
zeros and read as undefined.
written as zeros.
This field is a copy of the BCNT
field of TMD1 of the current
transmit descriptor.
These bits are read/write acces-
sible only when either the STOP
or the SPND bit is set. These bits
are unaffected by H_RESET,
S_RESET, or STOP.
zeros and read as undefined.
Current Transmit Status. This
field is a copy of bits 31-16 of
TMD1 of the current transmit
descriptor.
These bits are read/write acces-
sible only when either the STOP
or the SPND bit is set. These bits
are unaffected by H_RESET,
S_RESET, or STOP.
zeros and read as undefined.
Reserved locations. Read and
written as zeros.
field is a copy of the BCNT field of
RMD1 of the next receive de-
scriptor.
These bits are read/write acces-
sible only when either the STOP
or the SPND bit is set. These bits
are unaffected by H_RESET,
S_RESET, or STOP.
Description
Reserved locations. Written as
Reserved locations. Read and
Description
Description
Current Transmit Byte Count.
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