DS2155 datasheet(73/262 Pages) DALLAS

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DS2156

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SR4

Status Register 4

1Ch

Bit #

Name

RAIS-CI

RSAO

RSAZ

TMF

TAF

RMF

RCMF

RAF

Default

Bit 0/Receive Align Frame Event (RAF) (E1 Only). Set every 250µs at the beginning of align frames. Used to

alert the host that Si and Sa bits are available in the RAF and RNAF registers.

Bit 1/Receive CRC4 Multiframe Event (RCMF) (E1 Only). Set on CRC4 multiframe boundaries; continues to

set every 2ms on an arbitrary boundary if CRC4 is disabled.

Bit 2/Receive Multiframe Event (RMF)

E1 Mode: Set every 2ms (regardless if CAS signaling is enabled or not) on receive multiframe boundaries.

Used to alert the host that signaling data is available.

T1 Mode: Set every 1.5ms on D4 MF boundaries or every 3ms on ESF MF boundaries.

Bit 3/Transmit Align Frame Event (TAF) (E1 Only). Set every 250µs at the beginning of align frames. Used to

alert the host that the TAF and TNAF registers need to be updated.

Bit 4/Transmit Multiframe Event (TMF)

E1 Mode: Set every 2ms (regardless if CRC4 is enabled) on transmit multiframe boundaries. Used to alert

the host that signaling data needs to be updated.

T1 Mode: Set every 1.5ms on D4 MF boundaries or every 3ms on ESF MF boundaries.

Bit 5/Receive Signaling All-Zeros Event (RSAZ) (E1 Only). Set when over a full MF, time slot 16 contains

all 0s.

Bit 6/Receive Signaling All-Ones Event (RSAO) (E1 Only). Set when the contents of time slot 16 contains fewer

than three 0s over 16 consecutive frames. This alarm is not disabled in the CCS signaling mode.

Bit 7/Receive AIS-CI Event (RAIS-CI) (T1 Only). Set when the receiver detects the AIS-CI pattern as defined in

ANSI T1.403.

DS2155 Datasheet(PDF) 73 Page - Dallas Semiconductor