PM5364 pmc-sierra, PM5364 Datasheet - Page 210

• Manufacturer Part Number: PM5364
• Description: Tupp 2488 Assp Telecom Standard
• Manufacturer: pmc-sierra

13.9
13.10 HPOH Subsystem Operation
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2011334, Issue 7
Alternatively, the microprocessor can poll the UPDATEV field within the Configuration register
to detect the status of the connection memory page update logic. ‘1’ indicates copying in
progress and ‘0’ indicates copying complete.
Warning: Attempting a page copy while a page swap is pending can lead to corruption of both
online and offline memory pages if the page swap occurred while the page copy is in progress.
CCB and J0
In operation all 1080 words of the configuration RAM pages are utilized. This same
configuration is repeated 9 times to switch an entire 9720 byte OC-12 frame. Page swaps can
occur every frame. CMP input is sampled every frame at the per frame EJ0 location. If enabled,
FRAMEI will also occur every frame at the per frame EJ0 position. The OJ0FP output pulse
that is used to resynchronize system CML is a delayed version of the per frame EJ0.
Event Sequencing with respect to EJ0
The main reference point available is the FRAMEI interrupt status bit which indicates that
sampling of the CMP signal have occurred.
If CMP has changed, the PAGE_SWAP_PENDINGV will be asserted and correspondingly
PAGE_SWAP_PENDNGI will be asserted. This indicates that a page swap is pending.
The latency between when CMP is sampled until the actual page change occurs is one frame
plus a programmed delay in the top level register bits. When CMP is sampled the page change
pending flag is set if a page change is required. Connection memory page swaps can only occur
at frame boundaries. The page change pending flag will only be cleared when connection
memory page is swapped. If interrupt generation is enabled, an interrupt is generated when a
page change takes place. Therefore, caution must be taken when accessing the offline
connection memory page after a page swap request.
Attempting to write to the offline connection memory pages close to page swap boundary can
lead to corruption of both connection pages. Users are advised NOT to perform write accesses
when PAGE_SWAP_PENDINGV is active.
Also, users are advised NOT to perform page copy when PAGE_SWAP_PENDINGV is active.
Egress SVCA Operation
Refer to the description of the SVCA_R in the payload processing subsystem description
(sections 13.6.6 through 13.6.8). Bypass of the egress SVCA_R blocks is not supported.
The HPOH Subsystem has three modes of operation:
•
•
Normal Mode
Loopback Mode
TUPP™ 2488 ASSP Telecom Standard Product Data Sheet
Released
210