FTLX6611MCC and FTLX6614MCC T-XFP Product Specification
Finisar Corporation August 2015 Rev. B1 Page 10
Upon a power up, the module will go to a default wavelength (Finisar default channel is
1549.716nm) or the last channel set by the host. If Tx_DIS is asserted upon power up, the
laser will be disabled and the set wavelength will be cleared. Once the Tx_DIS is de-
asserted, the firmware will maintain the laser in an off state until the host sets the desired
ITU channel. If the module is powered-down before the ITU channel was set and
TX_DIS de-asserted, the module will re-start at the default channel. See the following
startup channel flowchart.
Flow Chart of Startup Channel
A desired wavelength can be commanded by the user by writing into Bytes 72 (MSB)
and 73 (LSB). Wavelength control command:
User input of Wavelength set point (in
units of 50 pm)
Monitor of Current Wavelength Error (in
units of 5 pm)
Thus for instance a target wavelength of 1556.55 nm would correspond to 79h (MSB)
written to Byte address 72 and 9Bh (LSB) written to Byte address 73. Alternatively a
desired frequency channel can be commanded by the user by writing into Bytes 112
(MSB) and 113 (LSB).
