Revision 5.01 – November 30, 2005
S5335 – PCI Bus Controller, 3.3V
Data Sheet
Target Requested Retries
Target Aborts
When the S5335 FIFO registers are accessed (S5335
as a target) and data is unavailable (empty FIFO) for
read transfers or cannot be accepted for write trans-
fers (full FIFO), the S5335 immediately terminates the
cycle by requesting a retry. The S5335 also initiates a
retry for Pass-Thru writes where the Add-On has not
completed the preceding Pass-Thru write by asserting
PTRDY#, and for Pass-Thru reads where the Add-On
cannot supply data within 8 PCI clocks (16 clocks for
the first data phase of a burst). A retry is requested by
a target asserting both STOP# and DEVSEL# while
TRDY# is deasserted. Figure 57 shows the behavior
of the S5335 when performing a target-initiated retry.
A target abort termination represents an error condi-
tion where no number of retries will produce a
successful target access. A target abort is uniquely
identified by the target deasserting DEVSEL# and
TRDY# while STOP# is asserted. When a target per-
forms an abort, it must also set bit 11 of its PCI Status
register. The S5335 configuration and operation regis-
ters never respond with a target abort when accessed.
If the S5335 encounters this condition when operating
as a PCI initiator, the S5335 sets bit 12 (received tar-
get abort) in the PCI Status register. Figure 58depicts
a target abort cycle.
Target termination types are summarized in Table 55.
Figure 57. Target-Initiated Retry
3
2
1
45
PCI CLOCK
FRAME #
IRDY#
(I)
(I)
(T)
(T)
TRDY#
STOP#
(T)
DEVSEL#
INITIATOR
SEQUENCES IRDY#
+ FRAME# TO RETURN
TARGET
RETRY
TO IDLE STATE
(I) = DRIVEN BY INITIATOR
(T) = DRIVEN BY TARGET
SIGNALED
Table 55. Target Termination Types
Termination DEVSEL# STOP# TRDY#
Comment
Disconnect
Retry
on
on
off
on
on
on
on
off
off
Data is transferred. Transaction needs to be reinitiated to complete.
Data was not transferred. Transaction should be tried later.
Data was not transferred. Fatal error.
Abort
AMCC Confidential and Proprietary
DS1657 101
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
