PM8621 datasheet(149/184 Pages) PMC

149 / 184 page

NSE-8G™ Standard Product Data Sheet

Preliminary

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use

148

Document ID: PMC-2010850, Issue 1

° If enabled, FRAMEI will occur every 4 frame at the internally flywheeled RC1FP

location.

12.9 SBI DS0 Mode Operation

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.

° This programs the DCB to use all 9720 location of the RAMs.

2. Program the MF_SWAP bits in DCB Configuration register (0x4C) to 10.

° 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.

12.10 SBI DS0 with CAS Mode Operation

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.

° This programs the DCB to use all 9720 location of the RAMs.

2. Program the MF_SWAP bits in DCB Configuration register (0x4C) to 11.

° 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.

PM8621 Datasheet(PDF) 149 Page - PMC-Sierra, Inc