The device and JESD204C interface
require a specific startup and alignment sequence. The order of that sequence is
listed in the following steps.
- Power-up or reset the
- Apply a stable device CLK signal
at the desired frequency.
- Perform a software reset by
toggling SOFT_RESET to 1. Wait at least 1 µs before continuing.
- Program JESD_EN = 0 to stop the
JESD204C 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
- 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 JESD204C state machine and allow the link to restart.
- The JESD204C 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.