Rainbow Electronics DS1876 - Manual (Page 64)

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DS1876
SFP Controller with Dual LDD Interface
Table 04h Register Descriptions
Table 04h, Register 80h–C7h: MODULATION LUT (MOD)
Table 02h, Register C8h–F7h: EMPTY
FACTORY DEFAULT 00h
READ ACCESS PW2 or (PW1 and RWTBL46)
WRITE ACCESS PW2 or (PW1 and RWTBL46)
A2h AND B2h MEMORY Different A2h and B2h memory locations
MEMORY TYPE Nonvolatile (EE)
80h–C7h 2 7 2 6 2 5 2 4 2 3 2 2 2 1 2 0
BIT 7 BIT 0
Digital value for the MOD1 DAC (A2h address) and MOD2 DAC (B2h address) outputs. The MODULATION LUT
is a set of registers assigned to hold the temperature profile for the MOD1 and MOD2 DACs. The temperature
measurement is used to index the LUT (TINDEX, Table 02h, Register 81h) in 2NC increments from -40NC to
+102NC, starting at 80h in Table 04h. Register 80h defines the -40NC to -38NC MOD output, Register 81h defines
-38NC to -36NC MOD output, and so on. Values recalled from this EEPROM memory table are written into the
MOD1 and MOD2 DACs (Table 02h, Registers C8h–C9h, CCh–CDh) locations that hold the values until the next
temperature conversion. The part can be placed into a manual mode (MOD1EN and MOD2EN bits, Table 02h,
Register 80h), where MOD1 and MOD2 DACs are directly controlled for calibration. If the temperature compen-
sation functionality is not required, program the entire Table 04h to the desired modulation setting.
FACTORY DEFAULT 00h
READ ACCESS N/A
WRITE ACCESS N/A
A2h AND B2h MEMORY N/A
MEMORY TYPE None
These registers do not exist.