Datasheet

____________________________________________________ DS34T101, DS34T102, DS34T104, DS34T108
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Figure 10-63. Interrupt Pin Logic
The TDMoP interrupts indicated in the Intpend regi
ster are of two types. The first type consists of interrupts
generated by a single source. The second type consists of interrupts that can originate from any of several possible
interrupt sources including the ETH_MAC, CW_bits_change, Rx_CAS_change, Tx_CAS_Change, and
JB_underrun interrupts.
The JBC_underrun inte
rrupts can be masked per timeslot by setting the appropriate bits in the
JBC_underrun_mask regi
sters.
The Tx_CAS_change i
nterrupts can be masked per timeslot by setting the appropriate bits in the
Tx_CAS_change_mask re
gisters.
The CW_bits_change interru
pts can be masked per bundle by setting the appropriate bits in the CW_bits_mask
registers. In addition, the fields of the control word that cause an interrupt when changed (L, R, M, FRG) can be
configured in the CW_bits_change_mask regi
ster.
When an interrupt is indicated on H_INT[0], the CPU sho
uld read the Intpend register to identify the interrupt
source and then proceed as follows:
Interrupt Type Interrupt Procedure
Single-source Interrupts
1. Clear the pending interrupt(s) by writing 1 to the corresponding
Intpend bit(s
).
2. Service the source of the interrupt.
Rx_CAS_change
1. Read the Rx_CAS_change bits in the Intpend register to determine
which port(s) are indicating Rx CAS change.
2. Clear the set Rx_CAS_change bits in the Intpend re
gister by writing
1 to them.
3. Read the corresponding Rx_CAS_change regi
ster(s) to determine
which timeslot(s) have been changed.
4. Clear the set bits in the Rx_CAS_change regi
ster(s) by writing 1 to
them.
5. Read the corresponding Rx CAS information from the Rx Line CAS
registers (section 11.4.10).
Tx_CAS_change
1. Read the Tx_CAS_change bits in the Intpend register to determine
which port(s) are indicating Tx CAS change.
2. Clear the set Tx_CAS_change bits in the Intpend re
gister by writing
1 to them.
3. Read the corresponding Tx_CAS_change regi
ster(s) to determine
which timeslot(s) have been changed.
4. Clear the set bits in the Tx_CAS_change regi
ster(s) by writing 1 to
them.
5. Read the appropriate Tx CAS information from the framers
(registers TS1 to TS16).