
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
354
If DC_EN is disabled and an overrun/underrun condition is reported for a
link, the link should be reset by writing to the tributary control register for
the tributary corresponding to that link. If DC_EN is set, then the tributary
will automatically be reset.
INSBI/EXSBI Programming Steps:
1. For each write access, wait until the BUSY bit in the Insert/Extract
Tributary RAM Indirect Access Control Register is clear. Note that the
BUSY bit might not be ready for up to 4.32 us after a Control RAM
access.
2. Once the BUSY bit is clear, write to the Insert/Extract Tributary RAM
Indirect Access Address Register specifying the SPE and tributary that
is about to be configured.
3. Then write into the Extract Tributary Control RAM Indirect Access
Data register to specify the desired control values for that tributary.
4. Next, write into the Extract Tributary RAM Indirect Access Control
register to specify whether this is to be a write or a read access, by
clearing or setting the WRB bit in this register.
The above 4 steps must be done and must be repeated for every
tributary access.
Tributary Configuration Sequences:
Configure all the Control RAM in both EXSBI and INSBI, following the
above four steps.
Enable the SPEs last by setting the SPEn_ENBL bits in the
SBI_BUS_CFG_REG.
12.3.2 Configuring Clock/Data Interface
The Clock/Data interface has 2 major modes, Channelized for E1/T1 traffic and
unchannelized for other traffic types.
Each link should be configured for channelized/unchannelized mode using the
RCAS/TCAS link configuration registers. If configuring channelized links, the
T1/E1 mode should be configured at the same time.