Datasheet

36 Maxim Integrated
SFP Controller for Dual Rx Interface
DS1877
Lower Memory, Register 70h: ALARM
3
Lower Memory, Register 6Fh: UPDATE
POWER-ON VALUE 00h
READ ACCESS All
WRITE ACCESS All and device hardware
A2h AND B2h MEMORY Different A2h and B2h memory locations
MEMORY TYPE Volatile
6Fh TEMP RDY VCC RDY RESERVED RESERVED RSSI RDY RESERVED RESERVED RSSIR
BIT 7 BIT 0
BITS 7,
6, 3
TEMP RDY, VCC RDY, RSSI RDY: Update of completed conversions. At power-on, these bits
are cleared and are set as each conversion is completed. These bits can be cleared so that a
completion of a new conversion is verified.
BITS 5, 4,
2, 1
RESERVED
BIT 0
RSSIR: RSSI range. Reports the range used for conversion update of RSSI.
0 = Fine range is the reported value.
1 = Coarse range is the reported value.
POWER-ON VALUE 10h
READ ACCESS All
WRITE ACCESS N/A
A2h AND B2h MEMORY Different A2h and B2h memory locations
MEMORY TYPE Volatile
70h TEMP HI TEMP LO VCC HI VCC LO RESERVED RESERVED RESERVED RESERVED
BIT 7 BIT 0
BIT 7
TEMP HI: High alarm status for temperature measurement.
0 = (default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 6
TEMP LO: Low alarm status for temperature measurement.
0 = (default) Last measurement was equal to or above threshold setting.
1 = Last measurement was below threshold setting.
BIT 5
VCC HI: High alarm status for V
CC
measurement.
0 = (default) Last measurement was equal to or below threshold setting.
1 = Last measurement was above threshold setting.
BIT 4
VCC LO: Low alarm status for V
CC
measurement. This bit is set when the V
CC
supply is below the
POA trip point value. It clears itself when a V
CC
measurement is completed and the value is above
the low threshold.
0 = Last measurement was equal to or above threshold setting.
1 = (default) Last measurement was below threshold setting.
BITS 3:0 RESERVED