8.3 Initialization Set Up
The device and JESD204 interface require a specific startup and alignment sequence. The general order of that sequence is listed in the following steps.
- Power-up or reset the device.
- Apply a stable device CLK signal at the desired frequency.
- Program JESD_EN = 0 to stop the JESD204B state machine and allow setting changes.
- Program CAL_EN = 0 to stop the calibration state machine and allow setting changes.
- Program the desired JMODE.
- Program the desired KM1 value. KM1 = K–1.
- Program SYNC_SEL as needed. Choose SYNCSE or timestamp differential inputs.
- Configure device calibration settings as desired. Select foreground or background calibration modes and offset calibration as needed.
- Program CAL_EN = 1 to enable the calibration state machine.
- Enable overrange via OVR_EN and adjust settings if desired.
- Program JESD_EN = 1 to re-start the JESD204B state machine and allow the link to restart.
- The JESD204B interface operates in response to the applied SYNC signal from the receiver.
- Program CAL_SOFT_TRIG = 0.
- Program CAL_SOFT_TRIG = 1 to initiate a calibration.