AM79C970A Advanced Micro Devices, AM79C970A Datasheet - Page 51

• Manufacturer Part Number: AM79C970A
• Description: PCnet-PCI II Single-Chip Full-Duplex Ethernet Controller for PCI Local Bus Product
• Manufacturer: Advanced Micro Devices

Master Initiated Termination
There are three scenarios besides normal completion of
a transaction where the PCnet-PCI II controller will ter-
minate the cycles it produces on the PCI bus.
Preemption During Non-Burst Transaction
When the PCnet-PCI II controller performs multiple
DEVSEL
FRAME
TRDY
IRDY
C/BE
REQ
GNT
CLK
PAR
Figure 20. Preemption During Non-Burst Transaction
AD
1
DEVSEL is sampled
2
P R E L I M I N A R Y
ADDR
0111
Am79C970A
3
PAR
non-burst transactions, it keeps REQ asserted until the
assertion of FRAME for the last transaction. When GNT
is removed, the PCnet-PCI II controller will finish the
current transaction and then release the bus. If it is not
the last transaction, REQ will remain asserted to regain
bus ownership as soon as possible.
4
DATA
BE
5
PAR
6
7
19436A-23
AMD
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