NSE-8G™ Standard Product Data Sheet
Preliminary
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.
12.7 Telecombus Mode Operation
In Telecombus mode operation, only 1080 words of the configuration RAM are utilized. This
same configuration is repeated nine times for switching the entire 9720 byte OC-12 frame. In this
mode, RC1FP is flywheeled internally every frame so that page swaps can also occur at this
frequency. The OC1FP output pulse that is used to resynchronize external TSBs occurs at every
4th frame.
To configure this mode of operation, use the following programming steps. Note, the order in
which these steps are followed is irrelevant.
1. Program the DCB Frame Size register (0x4A) to 1079.
°
This programs the DCB to use just 1080 location of the RAMs.
2. Program the DCB MF_SWAP bits in Configuration register (0x4C) to 00.
°
This will program the DCB to effect page changes at every 9720 byte frame when a page
swap request is received.
°
°
°
OC1FP will be output at every 4th frame.
CMP inputs will be sampled every frame at the internally flywheeled RC1FP location.
If enabled, FRAMEI will occur every frame at the internally flywheeled RC1FP location.
12.8 SBI Column Mode Operation
In SBI column mode operation, only 1080 rows of the configuration RAM is utilized, this same
configuration is repeated nine times for switching the entire 9720 byte OC12 frame and 36 times
to form the 4-frame multiframe. In this mode, RC1FP is flywheeled internally every fourth frame
so that page swap can also occur at this frequency. OC1FP output that is used to resynchronize
external TSBs also occurs at every fourth frame.
To configure this mode of operation, use the following programming steps. Note, the order in
which these steps are followed is irrelevant.
1. Program the DCB Frame Size register (0x04A) to 1079.
°
This programs the DCB to use just 1080 location of the RAMs.
2. Program the MF_SWAP bits in DCB Configuration register (0x04C) to 01.
°
This will program the DCB to effect page changes at every 4 x 9720 frame when a page
swap request is received.
°
°
OC1FP will be output at every 4 frame.
CMP inputs will be sampled every 4 frame at the internally flywheeled RC1FP location.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2010850, Issue 1
147
PMC [ PMC-SIERRA, INC ]
