S5935TFC AMCC [Applied Micro Circuits Corporation], S5935TFC Datasheet - Page 79

• Manufacturer Part Number: S5935TFC
• Description: PCI Product
• Manufacturer: AMCC [Applied Micro Circuits Corporation]

S5935 – PCI Product
ADD-ON PASS-THRU ADDRESS REGISTER (APTA)
ADD-ON PASS-THRU DATA REGISTER (APTD)
AMCC Confidential and Proprietary
Register
Name
Add-On
Address
Offset
Power-up
value
Attribute
Size
Register Name
Add-On
Address Offset
Power-up value
Attribute
Size
Add-On Pass-Thru Address
28h
XXXXXXXXh
Read Only
32 bits
Add-On Pass-Thru Data
2Ch
XXXXXXXXh
Read/Write
32 bits
This register, along with APTA described above, is employed when a
response is desired should one of the Base address decode regions become
selected during an active PCI bus cycle. When one of the base address
decode registers 1-4 encounters a PCI bus cycle which selects the region
defined by it, the APTA register will contain that current cycle’s active address
and the device asserts the signal PTATN# (Pass-Thru ATentioN). Wait states
are generated on the PCI bus until this register is read (PCI bus writes) or this
register is written (PCI bus reads).
This register is employed when a response is desired when one of the Base
address decode regions is selected during an active PCI bus cycle. When
one of the base address decode registers 1-4 encounters a PCI bus cycle
which selects the region defined by it, this device latches that current cycle’s
active address and asserts the signal PTATN# (Pass-Thru Attention). Wait
states are generated on the PCI bus until either data is transferred or the PCI
bus cycle is aborted by the initiator.
This register provides a method for “live” data (registered) transfers.
Intended uses include the emulating of other hardware as well as enabling
the connection of existing external hardware to interface to the PCI bus
through the S5935.
Revision 1.02 – June 27, 2006
Data Book
DS1527
79