PM8621 PMC-Sierra, Inc., PM8621 Datasheet - Page 149

• Manufacturer Part Number: PM8621
• Description: NSE-8G Standard Product Data Sheet Preliminary
• Manufacturer: PMC-Sierra, Inc.

12.10 SBI DS0 with CAS Mode Operation
12.9 SBI DS0 Mode Operation
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2010850, Issue 1
In SBI DS0 mode operation, all 9720 words of the configuration RAM are utilized. This same
configuration is repeated four times to switch the 4-frame multiframe. In this mode, RC1FP is
flywheeled internally every four frames so that page swaps can also occur at this frequency. A
pulse on the OC1FP output that is used to resynchronize external TSBs also occurs every four
frames.
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 9719.
2. Program the MF_SWAP bits in DCB Configuration register (0x4C) to 10.
In SBI DS0 with CAS mode operation, all 9720 words of the configuration RAM are utilized.
This same configuration is repeated 48 times to switch the 48 frame multiframe. In this mode,
RC1FP is flywheeled internally every 48th frame so that page swaps can also occur at this
frequency. A pulse on the OC1FP output that is used to resynchronize external TSBs also occurs
at every 48th 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 9719.
2. Program the MF_SWAP bits in DCB Configuration register (0x4C) to 11.
If enabled, FRAMEI will occur every 4 frame at the internally flywheeled RC1FP
location.
This programs the DCB to use all 9720 location of the RAMs.
This will program the DCB to effect page changes at every 4 x 9720 frame when a page
swap request is received.
OC1FP will pulse high at every 4th frame.
CMP inputs will be sampled every 4th frame at the internally flywheeled RC1FP
location.
If enabled, FRAMEI will occur every 4th frame at the internally flywheeled RC1FP
location.
This programs the DCB to use all 9720 location of the RAMs.
This will program the DCB to effect page changes at every 48 x 9720 frame when a page
swap request is received.
OC1FP will pulse every 48th frame.
NSE-8G™ Standard Product Data Sheet
Preliminary
148