AM79C971VCW Advanced Micro Devices, AM79C971VCW Datasheet - Page 141

• Manufacturer Part Number: AM79C971VCW
• Description: PCnet-FAST Single-Chip Full-Duplex 10/100 Mbps Ethernet Controller for PCI Local Bus
• Manufacturer: Advanced Micro Devices

CSR62: Previous Transmit Byte Count
Bit
31-16 RES
15-12 RES
11-0
CSR63: Previous Transmit Status
Bit
31-16 RES
15-0
CSR64: Next Transmit Buffer Address Lower
Bit
31-16 RES
15-0
CSR65: Next Transmit Buffer Address Upper
Bit
PXBC
Name
PXST
NXBAL
Name
Name
Name
Reserved locations. Written as
zeros and read as undefined.
Reserved locations.
Previous Transmit Byte Count.
This field is a copy of the BCNT
field of TMD1 of the previous
transmit descriptor.
Description
Reserved locations. Written as
zeros and read as undefined.
Previous Transmit Status. This
field is a copy of bits 31-16 of
TMD1 of the previous transmit
descriptor.
Reserved locations. Written as
zeros and read as undefined.
Contains the lower 16 bits of the
next transmit buffer address from
which the Am79C971 controller
will transmit an outgoing frame.
Read/Write accessible only when
either the STOP or the SPND bit
is set. These bits are unaffected
by H_RESET, S_RESET, or
STOP.
Read/Write accessible only when
either the STOP or the SPND bit
is set. These bits are unaffected
by H_RESET, S_RESET, or
STOP.
Read/Write accessible only when
either the STOP or the SPND bit
is set. These bits are unaffected
by H_RESET, S_RESET, or
STOP.
Description
Description
Description
P R E L I M I N A R Y
Am79C971
31-16 RES
15-0
CSR66: Next Transmit Byte Count
Bit
31-16 RES
15-12 RES
11-0
CSR67: Next Transmit Status
Bit
31-16 RES
15-0
7-0
NXBAU
Name
NXBC
NXST
RES
Name
Read/Write accessible only when
either the STOP or the SPND bit
is set. These bits are unaffected
by H _ R E S E T, S _ R E S E T, o r
STOP.
Reserved locations. Written as
zeros and read as undefined.
Contains the upper 16 bits of the
next transmit buffer address from
which the Am79C971 controller
will transmit an outgoing frame.
Description
Reserved locations. Written as
zeros and read as undefined.
Reserved locations. Read and
written as zeros.
Next Transmit Byte Count. This
field is a copy of the BCNT field of
TMD1 of the next transmit de-
scriptor.
Read/Write accessible only when
either the STOP or the SPND bit
is set. These bits are unaffected
by H_RESET, S_RESET, or
STOP.
Reserved locations. Written as
zeros and read as undefined.
Next Transmit Status. This field is
a copy of bits 31-16 of TMD1 of
the next transmit descriptor.
Read/Write accessible only when
either the STOP or the SPND bit
is set. These bits are unaffected
by H_RESET, S_RESET, or
STOP.
Reserved locations. Read and
written as zeros. Accessible only
when either the STOP or the
SPND bit is set.
Description
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