AM79C976 Advanced Micro Devices, AM79C976 Datasheet - Page 58

• Manufacturer Part Number: AM79C976
• Description: PCnet-PRO 10/100 Mbps PCI Ethernet Controller
• Manufacturer: Advanced Micro Devices

P R E L I M I N A R Y
If a receive buffer does not end on a DWord boundary,
the Am79C976 controller will perform a non-DWord
write on the last transfer to the buffer. Figure 27 shows
CLK
the final three FIFO DMA transfers to a receive buffer.
1
2
3
4
5
6
Since there were only 9 bytes of space left in the re-
FRAME
ceive buffer, the Am79C976 controller bursts three data
phases. The first two data phases write a full DWord,
the last one only writes a single byte.
ADD
AD
DATA
DATA
DATA
C/BE
0111
0001
0000
PAR
PAR
PAR
PAR
IRDY
TRDY
DEVSEL
REQ
GNT
DEVSEL is sampled
22929B28
58
Am79C976
8/01/00