this implements accessing array members in an ArduinoJSON object
following the FirebaseJson syntax. the FirebaseJson lib was previously
removed to save flash memory, and logic was implemented to find a JSON
node using the FirebaseJson path syntax, restoring the functionality.
however, array access was not implemented.
this change also addresses leading and trailing and double forward
slashes in the path expression.
moreover, much more expressive error messages are now generated in case
the path could not be resolved.
mbedtls is already integral part of the firmware. use it in favor of
rweather/Crypto library to calculate a sha256 checksum of a string, as
used in the HTTP power meter implementation.
we used this library solely to interpret the answer of an HTTP web
server as JSON and find a particular value using a path expression in
the HTTP power meter implementation.
since we ran out of flash memory on non-S3 ESP32, we need to cut some
corners. removing FirebaseJson is the last low-hanging fruit that we
currently know of. we can get rid of it by using ArduinoJson (which is
already integral part of the firmware) and implementing a custom logic
to extract a value based on a path expression.
other than the FirebaseJson path "finder", the new implementation
only knows how to access sub-keys delimited by a forward slash. in
particular, accessing array members is not supported any more. I am
hoping that this is simply not an issue. if so, we will have users
complaining and we can add this functionality in a later release.
when calculating efficiency, we need to take into account that the load
might also sink a significant amount of current and power, which adds to
the total output of the charge controller.
merge upstream tag v24.4.12, resolve conflicts (helgeerbe), fix eslint errors (schlimmchen) and adopt new web api method to save code duplication (schlimmchen).
this allows to use two VE.Direct interfaces, as there is no conflict
regarding HW serial port 2 after making the battery interfaces use
serial port 0 on devices with USB CDC. on those chips HW serial 0 is
free to be used since serial messages are written through the USB
interface directly.
we found that the inverter sometimes stops responding to commands,
especially to the "start producing" command. we now count the number of
consecutive timeouts when trying to send a new limit or power state
commands. after two timeouts were recorded, every additional timeout
will send a restart command to the inverter.
as a last resort, if the counter keeps climbing, the DTU is restarted.
notice that this only targets unresponsive inverters which are
reachable. unreachable inverters are not restarted and do not cause a
DTU reboot. this is important for solar-driven inverters, which are
unreachable during the night. the DPL will not calculate a new limit and
hence the updateInverter() method will do nothing while the target
inverter is unreachable.
publish the timeout counter to MQTT for monitoring purposes.
avoid performing a calculation based on a (slightly) outdated power
meter reading, which was aquired just before the limit was actually
applied by the inverter, but which was received by OpenDTU-OnBattery
after the inverter stats.
without a power meter configured, the DPL now sets the base load as the
inverter limit if the battery charge allows it. it also takes
solar-passthrough into account, i.e., if the battery is in a charge
cycle but the solar output (Victron MPPT) is significant, the solar
power will be used up until the base load. if the battery reaches the
full solar passthrough threshold, the DPL will match the inverter limit
to the MPPT solar output.
on power meter issues (usually a timeout), keep the inverter enabled and
make it produce the configured base load limit if the battery can be
discharged. that should be okay since the base load config value is
expected to be small and a little less than the actual household base
load, i.e., if this amount of power is produced, the household will
consume it in any case and no energy is fed into the grid.
