Effectively flips all values related to the directionality of current
through the TEC, including current maximums. The reversed status is
stored in the flash store and will be loaded on reset once saved.
The command is "pwm <ch> polarity <normal/reversed>", where the "normal"
polarity is indicated by the front panel markings.
This is needed for IDC cable connections to the Sinara 5432 DAC
"Zotino", since the TEC pins of the 10-pin connector on the Thermostat
and Zotino have opposite polarities.
As the report mode command breaks the send-receive architecture model of
the command interface, and is deemed an anti-feature, making clients
difficult to write, remove it from the firmware entirely.
* Fix wrong calibration of VREF on startup. Caused new v2.2.2 boards to
wrongly calibrate the zero-point to ~2.2 V instead of 1.5 V.
* Fix bootloop on some boards.
* Adjust watchdog interval accordingly.
Follow ARTIQ, and in this project lets us include the version number
directly in flake.nix instead of linking to the toml file of a specific
release date, as we use stable Rust.
Also, from nixpkgs manual:
both oxalica's overlay and fenix better integrate with nix and cache
optimizations. Because of this and ergonomics, either of those
community projects should be preferred to the Mozilla's Rust overlay
(nixpkgs-mozilla).
The REF pin of the MAX1968 on hardware revisions v2.x is missing a
buffer, loading the pin on every CPU ADC read. Avoid reading from it and
leave the pin floating on affected hardware revisions, and return the
nominal 1.5V instead.
Thermostats v2.2 and below have a noisy and offset feedback current
`tec_i` caused by missing hardware on 2 MAX1968 TEC driver pins:
1. A missing RC filter on the ITEC pin that would have isolated CPU
sampling pulses from the signal; and
2. Some missing buffering on the VREF pin that would have avoided
loading the VREF signal, preventing voltage drops from the nominal 1.5V.
Since the resulting signal `tec_i` derived from these two signals can
have an error of around +/- 100mA, and readback may affect the stability
performance of the Thermostat, disable current readback entirely on
affected hardware revisions for now.
See https://github.com/sinara-hw/Thermostat/issues/117 and
https://github.com/sinara-hw/Thermostat/issues/120.
On hardware revisions v3.x and above, this would be fixed.
Put SocketState initialisation logic in new. This avoids using an unsafe
and unnerving MaybeUninit::uninit().assume_init() to initialise an
array, which the compiler yells at since it causes undefined behavior.
Since VREF is an implementation detail, there shouldn't be a need to
include it in reports.
The ChannelState vref is removed along with it as its only use was to
save VREF measurements for later reporting.
Change the behaviour of LED L3 to turn off only when all channels have
PID disengaged, as opposed to when any channel disengages PID.
Otherwise, when disengaging PID on a Thermostat that has had both
channels engaged in PID, the LED would turn off, even when PID is still
engaged on the other channel.
This lets the LED better reflect the status of the Thermostat as a
whole, as it would stay on as long as PID is engaged on at least one
channel.
