DS26514DK Maxim Integrated Products, DS26514DK Datasheet - Page 64

• Manufacturer Part Number: DS26514DK
• Description: Power Management Modules & Development Tools 4-Port T1-E1-J1 Tran Transceiver Demo Kit
• Manufacturer: Maxim Integrated Products

Specifications of DS26514DK

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.9.7.1 Status and Information Bit Operation
When a particular event has occurred (or is occurring), the appropriate bit in one of these registers will be set to a
one. Status bits may operate in either a latched or real-time fashion. Some latched bits may be enabled to generate
a hardware interrupt via the INTB signal.
9.9.7.1.1 Real-Time Bits
Some status bits operate in a real-time fashion. These bits are read-only and indicate the present state of an alarm
or a condition. Real-time bits will remain stable, and valid during the host read operation. The current value of the
internal status signals can be read at any time from the real-time status registers without changing any the latched
status register bits.
9.9.7.1.2 Latched Bits
When an event or an alarm occurs and a latched bit is set to a one, it will remain set until cleared by the user.
These bits typically respond on a change-of-state for an alarm, condition, or event; and operate in a read-then-write
fashion. The user should read the value of the desired status bit, and then write a 1 to that particular bit location in
order to clear the latched value (write a 0 to locations not to be cleared). Once the bit is cleared, it will not be set
again until the event has occurred again.
9.9.7.1.3 Mask Bits
Some of the alarms and events can be either masked or unmasked from the interrupt pin via the Receive Interrupt
Mask Registers (RIM1, RIM3, RIM4, RIM5, RIM7). When unmasked, the INTB signal will be forced low when the
enabled event or condition occurs. The INTB pin will be allowed to return high (if no other unmasked interrupts are
present) when the user reads then clears (with a write) the alarm bit that caused the interrupt to occur. Note that
the latched status bit and the INTB pin will clear even if the alarm is still present.
Note that some conditions may have multiple status indications. For example, receive loss of frame (RLOF)
provides the following indications:
Rev: 101608
RRTS1.0
(RLOFD)
(RLOFC)
(RLOF)
RLS1.0
RLS1.4
Real-time indication that the receiver is not synchronized
with incoming data stream. Read-only bit that remains high
as long as the condition is present.
Latched indication that the receiver has loss
synchronization since the bit was last cleared. Bit will clear
when written by the user, even if the condition is still
present (rising edge detect of RRTS1.0).
Latched indication that the receiver has reacquired
synchronization since the bit was last cleared. Bit will clear
when written by the user, even if the condition is still
present (falling edge detect of RRTS1.0).
DS26514 4-Port T1/E1/J1 Transceiver
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