am79c970 Advanced Micro Devices, am79c970 Datasheet - Page 99

• Manufacturer Part Number: am79c970
• Description: Pcnettm-pci Single-chip Ethernet Controller For Pci Local Bus
• Manufacturer: Advanced Micro Devices

15–0 NNXDAU
CSR40: Current Receive Byte Count
Bit
31–16 RES
15–12 RES
11–0
CSR41: Current Receive Status
Bit
31–16 RES
15–8
7–0
CSR42: Current Transmit Byte Count
Bit
31–16 RES
15–12 RES
11–0
1-966
AMD
CRBC
CRST
CXBC
Name
Name
Name
RES
Contains the upper 16 bits of the
next next transmit descriptor ad-
dress pointer.
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Description
Reserved locations. Written as
ZEROs and read as undefined.
Reserved locations. Read and
written as ZERO.
Current Receive Byte Count.
This field is a copy of the BCNT
field of RMD1 of the current re-
ceive descriptor.
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Description
Reserved locations. Written as
ZEROs and read as undefined.
Current Receive Status. This
field is a copy of bits 31–24 of
RMD1 of the current receive
descriptor.
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Reserved locations. Read and
written as ZERO.
Description
Reserved locations. Written as
ZEROs and read as undefined.
Reserved locations. Read and
written as ZERO.
Current Transmit Byte Count.
This field is a copy of the BCNT
field of TMD1 of the current trans-
mit descriptor.
by
by
by
H_RESET,
H_RESET,
H_RESET,
P R E L I M I N A R Y
Am79C970
CSR43: Current Transmit Status
Bit
31–16 RES
15–8
7–0
CSR44: Next Receive Byte Count
Bit
31–16 RES
15–12 RES
11–0
CSR45: Next Receive Status
Bit
31–16 RES
15–8
7–0
NRBC
NRST
CXST
Name
Name
Name
RES
RES
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Description
Reserved locations. Written as
ZEROs and read as undefined.
Current Transmit Status. This
field is a copy of bits 31–24 of
TMD1 of the current transmit
descriptor.
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Reserved locations. Read and
written as ZERO.
Description
Reserved locations. Written as
ZEROs and read as undefined.
Reserved locations. Read and
written as ZERO.
Next Receive Byte Count. This
field is a copy of the BCNT field of
RMD1 of the next receive
descriptor.
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Description
Reserved locations. Written as
ZEROs and read as undefined.
Next Receive Status. This field is
a copy of bits 31–24 of RMD1 of
the next receive descriptor.
Read/write accessible only when
STOP bit is set. These bits are
unaffected
S_RESET or STOP.
Reserved locations. Read and
written as ZERO.
by
by
by
by
H_RESET,
H_RESET,
H_RESET,
H_RESET,