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PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
PM7341 S/UNI-IMA-84
DATASHEET
PMC-2000223
ISSUE 4
INVERSE MULTIPLEXING OVER ATM
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
352
12.3 Configuring the S/UNI-IMA-84
12.3.1 Configuring SBI Interface
In SBI mode the following items need to be properly configured:
The SPE type for each of the 3 SBI SPEs
SPE type can be E1, T1, or DS3 and is configured by setting SPEn_TYP
bits in the SBI Bus Configuration Register (SBI_BUS_CFG_REG) to the
appropriate value. All SPEs_TYP are default to T1 type.
Each SPE must be enabled or disabled by writing appropriate value into
SPEn_ENBL bit in the SBI Bus Configuration Register. All SPEs default to
being disabled.
Set the proper operation mode by writing 0x0080 to the SBI Extract Master
Interrupt Status Register
Tributary type for each tributary.
The tributary type must be configured to be Framed without CAS. This is
configured by setting TRIB_TYP to “01b” in the Extract/Insert. Tributary
Control Register inside the INSBI/EXSBI for that tributary. The TRIB_TYP
default value of “00b” is not supported
A tributary can float or be locked to the SBI frame structure. Only floating
tributaries are supported
SBI Error Checking and Reporting
The following errors can be detected on a per link basis: FIFO overrun,
FIFO underrun, and SBI parity error. These all can be enabled/disabled in
the Insert/Extract Control Register. These errors result in either the
SBI_DROP_INTR or SBI_ADD_INTR output being set.
Parity detection is done only on the drop bus, which is done by the
EXSBI block. Parity can be configured to be odd or even, and it is
default to be odd parity.