Datasheet

DS1878
SFP+ Controller with Digital LDD Interface
______________________________________________________________________________________ 29
POR OR TXD
READ TXPOR
3-WIRE STATE MACHINE
READ TXPOR
CONTROL/STATUS
INITIALIZATION
WAIT FOR MOD
(SET MOD_FLAG)
WRITE MOD
(RESET FLAGS)
TXD_STANDBY
(SET TXD_FLAG)
TXPOR = = 1?
MANMODE = = 1?
TXD_FLAG = = 1?
OR MOD_FLAG = 1?
OR DIS3W = 1?
BIASINC = = 1?
WAIT FOR BIAS
READ/WRITE
MANMODE
STANDBY
INCREMENT BIAS
CONTROL/STATUS
UPDATE
MODINC = = 1?
BIASINC = = 1?
TEMP_CONV = = 1?
AND DIS3W = 0
APC_BINARY = = 0?
TXD_ext = = 0?
TXPOR = = 1?
TXD = = 0?
TXD_FLAG = = 1?
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
MODINC = = 1?
YES
DIS3W = 1?
OR BIAS_MANUAL = 1?
TXD_FLAG = = 1?
OR MOD_FLAG = 1
INCREMENT
MODULATION
YES
YES
Figure 19. 3-Wire State Machine