Digitizer and packetizer controller

The digitizer controller configures MPIfR digitizer/packetizer hardware over KATCP and publishes one versioned voltage stream per polarization. It is a streaming control pipeline: it normally enters streaming after capture starts even though the bulk data bypasses its container.

The implementation has historically lived in mpikat and is being packaged as the EDD.digitizer_packetizer_controller collection. Verify the role and stream-format version in the site inventory; older provisions commonly use MPIFR_EDD_Packetizer:1 while newer consumers use version 2.

Main configuration

Key	Meaning
bit_depth	Hardware sample depth; supported values depend on firmware, commonly 8 or 12 bits.
sampling_rate	ADC sampling rate in Hz.
predecimation_factor	Hardware decimation, commonly 1, 2, 4, or 8. Effective output sample rate is sampling_rate / predecimation_factor.
flip_spectrum	Correct the frequency orientation for the selected Nyquist zone.
invert_1pps	Select the hardware-specific 1-PPS sampling sense.
noise_diode_pattern	Mapping with on percentage and period in seconds. It may be changed at measurement prepare.
sync_time	Future Unix epoch for synchronization; zero requests automatic choice.
force_reconfigure / max_sync_age	Control whether an otherwise unchanged device is reconfigured.
skip_packetizer_config / dummy_configure	Development controls that must not be enabled accidentally in production.

Associate the role with an inventory device entry containing the management endpoint and hardware interfaces. Do not control the same packetizer from a second tool while EDD owns it: the controller remembers its previous command rather than continuously reconstructing the complete hardware state.

Before capture, verify output addresses, effective sample rate, bit depth, polarization mapping, spectrum orientation, synchronization epoch, packet loss, and noise-diode timing from downstream data rather than control replies alone.