docs: Polish shield and sensor pages with usage examples and API detail.

Across the shield pages (battery, can-rs232, can, gigabit-poe, lcd,
pir, poe, rs422-rs485, touch-lcd, wifi) and sensor pages (flir-boson,
flir-lepton, genx320, mt9v024, multispectral-event,
multispectral-thermal-ov5640, ov5640, pag7936, ps5520):

- Drop "compatible with all OpenMV Cams" / FPS marketing bullets
  in favor of board-supported notes and concrete spec rows.
- Add full Usage sections with worked examples — touch overlay
  with FT6X36, Lepton temperature measurement (low + high range),
  PAG7936/OV5640 thermal overlay with optional GPU homography,
  GENX320 histogram + event modes (calibration, AFK, biases, STC,
  desktop streaming), and standalone OV5640 JPEG capture.
- Cross-reference API symbols throughout (csi.CSI, csi.IOCTL_*,
  image.PALETTE_*, Image.draw_image / draw_event_histogram, etc.).
- Expand library/omv.csi.rst with descriptions for all GENX320
  IOCTLs, bias presets, individual biases, STC modes, event-type
  constants, and the LEPTON ioctls.
- Normalize "5MP" capitalization across sensor and quickref pages.
- Convert per-board availability list in library/index.rst to
  rubrics so they don't clutter the right-side TOC.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: kwagyeman

docs/library/index.rst

@@ -210,8 +210,7 @@ on each board. All the modules in *Common*, *Frozen Python helpers*, and
 *Networking helpers* (above) are available on every camera board unless
 otherwise noted.
 
-OPENMV_N6 (STM32N6)
-^^^^^^^^^^^^^^^^^^^
+.. rubric:: OPENMV_N6 (STM32N6)
 
 OpenMV N6 (STM32N6 — STMicroelectronics' first NPU-equipped MCU):
 
@@ -220,8 +219,7 @@ OpenMV N6 (STM32N6 — STMicroelectronics' first NPU-equipped MCU):
 * :mod:`ssd1306` — OLED driver
 * :mod:`tb6612` — TB6612 motor driver
 
-OPENMV_AE3 (Alif Ensemble E3)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: OPENMV_AE3 (Alif Ensemble E3)
 
 OpenMV AE3 (Alif Ensemble E3 MCU):
 
@@ -230,8 +228,7 @@ OpenMV AE3 (Alif Ensemble E3 MCU):
 * :mod:`romfs` — ROMFS helper utilities
 * :mod:`pca9674a` — PCA9674A I2C expander driver
 
-OPENMV_RT1060 (i.MX RT1060)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: OPENMV_RT1060 (i.MX RT1060)
 
 OpenMV RT1060:
 
@@ -244,8 +241,7 @@ OpenMV RT1060:
 * :mod:`tb6612` — TB6612 motor driver
 * :mod:`pca9674a` — PCA9674A I2C expander driver
 
-OPENMVPT (Pure Thermal, STM32H7 + DVI/HDMI)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: OPENMVPT (Pure Thermal, STM32H7 + DVI/HDMI)
 
 OpenMV Pure Thermal:
 
@@ -260,8 +256,7 @@ OpenMV Pure Thermal:
 * :mod:`ssd1306` — OLED driver
 * :mod:`tb6612` — TB6612 motor driver
 
-OPENMV2 / OPENMV3 / OPENMV4 / OPENMV4P (STM32)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: OPENMV2 / OPENMV3 / OPENMV4 / OPENMV4P (STM32)
 
 Legacy STM32-based OpenMV camera boards:
 
@@ -274,8 +269,7 @@ Legacy STM32-based OpenMV camera boards:
 * :mod:`ssd1306` — OLED driver
 * :mod:`tb6612` — TB6612 motor driver
 
-ARDUINO_GIGA (STM32H7 + touchscreen)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: ARDUINO_GIGA (STM32H7 + touchscreen)
 
 Arduino Giga R1 WiFi:
 
@@ -287,8 +281,7 @@ Arduino Giga R1 WiFi:
 * :mod:`gt911` — GT911 5-point capacitive touch controller
 * :mod:`ft5x06` — capacitive touchscreen driver
 
-ARDUINO_PORTENTA_H7 (STM32H7)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: ARDUINO_PORTENTA_H7 (STM32H7)
 
 Arduino Portenta H7:
 
@@ -302,8 +295,7 @@ Arduino Portenta H7:
 * :mod:`ssd1306` — OLED driver
 * :mod:`tb6612` — TB6612 motor driver
 
-ARDUINO_NICLA_VISION (STM32H7)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: ARDUINO_NICLA_VISION (STM32H7)
 
 Arduino Nicla Vision:
 
@@ -315,8 +307,7 @@ Arduino Nicla Vision:
 * :mod:`onewire` — 1-Wire bus protocol
 * :mod:`neopixel` — control of WS2812 / NeoPixel LEDs
 
-ARDUINO_NANO_33_BLE_SENSE (Nordic nRF52840)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: ARDUINO_NANO_33_BLE_SENSE (Nordic nRF52840)
 
 Arduino Nano 33 BLE Sense — board-specific :doc:`imu <imu>` wrapper
 that selects between the LSM9DS1 (Rev 1) and BMI270 + BMM150 (Rev 2)
@@ -334,8 +325,7 @@ sensor sets, plus:
 * :mod:`ds18x20` — DS18x20 temperature sensor driver
 * :mod:`neopixel` — control of WS2812 / NeoPixel LEDs
 
-ARDUINO_NANO_RP2040_CONNECT / RPI_PICO (RP2)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. rubric:: ARDUINO_NANO_RP2040_CONNECT / RPI_PICO (RP2)
 
 RP2040-based boards. The Arduino Nano RP2040 Connect adds a few extra
 companion-chip drivers; the Raspberry Pi Pico ships only with the core

docs/library/omv.csi.rst

@@ -885,149 +885,253 @@ Constants
 .. data:: IOCTL_GENX320_SET_BIASES
    :type: int
 
-   Sets the GENX320 sensor biases to a preset. See `CSI.ioctl`.
+   Sets the GENX320 sensor biases to one of the
+   ``GENX320_BIASES_*`` presets. See `CSI.ioctl`. After
+   `CSI.reset` the driver applies `csi.GENX320_BIASES_LOW_NOISE`,
+   not `csi.GENX320_BIASES_DEFAULT` — use this ioctl to switch to
+   a different preset when the application needs more sensitivity
+   or bandwidth.
 
 .. data:: GENX320_BIASES_DEFAULT
    :type: int
 
-   Default biases for the GENX320 camera sensor.
+   GenX320 datasheet defaults — balanced sensitivity, noise, and
+   bandwidth for general scenes.
 
 .. data:: GENX320_BIASES_LOW_LIGHT
    :type: int
 
-   Low light biases for the GENX320 camera sensor.
+   Tuned for low-light conditions — both contrast thresholds
+   loosened for higher sensitivity, FO lowered, HPF disabled so
+   slow brightness changes still register.
 
 .. data:: GENX320_BIASES_ACTIVE_MARKER
    :type: int
 
-   Active marker biases for the GENX320 camera sensor.
+   Tuned for tracking high-contrast blinking LEDs (active markers)
+   — contrast thresholds raised so only sharp transitions trigger,
+   FO and HPF cranked high to maximize bandwidth and reject slow
+   ambient drift, REFR=0 so every blink edge is captured.
 
 .. data:: GENX320_BIASES_LOW_NOISE
    :type: int
 
-   Low noise biases for the GENX320 camera sensor.
+   Driver default — lower sensitivity than ``DEFAULT`` (raised
+   contrast thresholds) and a lower FO for less background-noise
+   activity. Best for static or slow scenes where false events
+   would dominate.
 
 .. data:: GENX320_BIASES_HIGH_SPEED
    :type: int
 
-   High speed biases for the GENX320 camera sensor.
+   Tuned for fast-motion scenes — higher FO for wider pixel
+   bandwidth, higher HPF to reject slow changes, higher REFR for
+   a longer dead time after each event so the readout doesn't
+   saturate.
 
 .. data:: IOCTL_GENX320_SET_BIAS
    :type: int
 
-   Sets a single GENX320 camera sensor bias. See `CSI.ioctl`.
+   Sets a single GENX320 sensor bias to a DAC value. Pass a
+   ``GENX320_BIAS_*`` constant (`csi.GENX320_BIAS_DIFF_OFF`,
+   `csi.GENX320_BIAS_DIFF_ON`, `csi.GENX320_BIAS_FO`,
+   `csi.GENX320_BIAS_HPF`, or `csi.GENX320_BIAS_REFR`) and an
+   integer DAC value. Each bias is independent — call this ioctl
+   repeatedly to tweak only the biases you need after applying a
+   preset. See `CSI.ioctl`.
 
 .. data:: GENX320_BIAS_DIFF_OFF
    :type: int
 
-   Selects the GENX320 DIFF OFF bias.
+   Negative comparator contrast threshold — controls how much a
+   pixel has to darken before a `csi.PIX_OFF_EVENT` fires. Lower
+   value = more sensitive (more events).
 
 .. data:: GENX320_BIAS_DIFF_ON
    :type: int
 
-   Selects the GENX320 DIFF ON bias.
+   Positive comparator contrast threshold — controls how much a
+   pixel has to brighten before a `csi.PIX_ON_EVENT` fires. Lower
+   value = more sensitive (more events).
 
 .. data:: GENX320_BIAS_FO
    :type: int
 
-   Selects the GENX320 FO bias.
+   Pixel low-pass cut-off frequency — trades pixel bandwidth
+   (speed/latency) against background-noise activity. Higher
+   value = faster pixel response, more noise.
 
 .. data:: GENX320_BIAS_HPF
    :type: int
 
-   Selects the GENX320 HPF bias.
+   Pixel high-pass cut-off frequency — rejects slow brightness
+   changes. Higher value = slower changes filtered out (only
+   fast transitions register).
 
 .. data:: GENX320_BIAS_REFR
    :type: int
 
-   Selects the GENX320 REFR bias.
+   Pixel refractory period — dead time after a pixel emits an
+   event during which it cannot fire again. Higher value =
+   longer dead time, fewer events from a busy pixel.
 
 .. data:: IOCTL_GENX320_SET_AFK
    :type: int
 
-   Sets the GENX320 anti-flicker filter. See `CSI.ioctl`.
+   Sets the GENX320 anti-flicker (AFK) filter, which rejects
+   events from pixels toggling at a periodic frequency band
+   (fluorescent lighting, LED-driven displays, etc.). Pass
+   ``enable`` (1 to enable, 0 to disable) and, when enabling,
+   the band edges in hertz: ``(enable, freq_low_hz, freq_high_hz)``.
+   See `CSI.ioctl`.
 
 .. data:: IOCTL_GENX320_SET_STC
    :type: int
 
-   Sets the GENX320 spatio-temporal contrast filter mode. See `CSI.ioctl`.
+   Sets the GENX320 spatio-temporal contrast (STC) filter mode.
+   Pass a ``GENX320_STC_*`` constant
+   (`csi.GENX320_STC_DISABLE`, `csi.GENX320_STC_ONLY`,
+   `csi.GENX320_STC_TRAIL_ONLY`, `csi.GENX320_STC_TRAIL`)
+   followed by the threshold(s) the mode requires (in
+   milliseconds). See `CSI.ioctl`.
 
 .. data:: GENX320_STC_DISABLE
    :type: int
 
-   Disable the GENX320 STC/trail filter.
+   Disable the GENX320 STC/trail filter — every event passes
+   through.
 
 .. data:: GENX320_STC_ONLY
    :type: int
 
-   Enable only the spatio-temporal contrast filter on the GENX320.
+   *Keeps the second event of a burst*; drops the first event
+   and any later events. Takes one parameter, ``stc_threshold``
+   in milliseconds — events within that window of a prior event
+   on the same pixel are considered part of the same burst.
 
 .. data:: GENX320_STC_TRAIL_ONLY
    :type: int
 
-   Enable only the trail filter on the GENX320.
+   *Keeps the first event of a burst*; drops subsequent events
+   on the same pixel until ``trail_threshold`` has elapsed. Takes
+   one parameter, ``trail_threshold`` in milliseconds.
 
 .. data:: GENX320_STC_TRAIL
    :type: int
 
-   Enable both the STC and trail filters on the GENX320.
+   *Keeps the first event of a burst plus subsequent edges* —
+   combines `csi.GENX320_STC_ONLY` and `csi.GENX320_STC_TRAIL_ONLY`.
+   Takes two parameters, ``stc_threshold`` and ``trail_threshold``
+   (both ms); the sensor requires the two to stay within roughly
+   a 13:1 ratio.
 
 .. data:: IOCTL_GENX320_SET_MODE
    :type: int
 
-   Sets the GENX320 camera sensor operating mode. See `CSI.ioctl`.
+   Sets the GENX320 operating mode. Pass `csi.GENX320_MODE_HISTO`
+   for the on-chip event histogram (the cam behaves like a
+   regular grayscale camera at the configured framerate) or
+   `csi.GENX320_MODE_EVENT` followed by the row-axis length of
+   the event ``ndarray`` (a power of two between 1024 and
+   65536) for raw event streaming. See `CSI.ioctl`.
 
 .. data:: GENX320_MODE_HISTO
    :type: int
 
-   Sets the GENX320 to histogram mode.
+   Histogram mode — events are accumulated on-chip into per-pixel
+   bins and reported as a 320x320 grayscale frame at the
+   configured rate (~20-350 FPS). The cam looks like a regular
+   camera, so all the standard image-processing routines work
+   directly.
 
 .. data:: GENX320_MODE_EVENT
    :type: int
 
-   Sets the GENX320 to event mode.
+   Event mode — bypasses the on-chip histogram and streams raw
+   events into a numpy ``ndarray`` with microsecond timestamps,
+   for applications that need full temporal detail rather than a
+   pre-binned frame.
 
 .. data:: IOCTL_GENX320_READ_EVENTS
    :type: int
 
-   Populates an ndarray with event information from the GENX320. See `CSI.ioctl`.
+   Reads raw events into a uint16 ``ndarray`` of shape
+   ``(EVT_res, 6)`` (with ``EVT_res`` matching the buffer size
+   passed to `csi.IOCTL_GENX320_SET_MODE`). The columns are
+   ``[0]`` event type (`csi.PIX_OFF_EVENT`, `csi.PIX_ON_EVENT`,
+   `csi.EXT_TRIGGER_RISING`/``FALLING``,
+   `csi.RST_TRIGGER_RISING`/``FALLING``), ``[1]`` seconds
+   timestamp, ``[2]`` milliseconds, ``[3]`` microseconds,
+   ``[4]`` X coord (0-319), ``[5]`` Y coord (0-319). Returns the
+   number of events written into the buffer, leaving older rows
+   beyond that count untouched. See `CSI.ioctl`.
 
 .. data:: IOCTL_GENX320_CALIBRATE
    :type: int
 
-   Automatically turns off hot pixels on the GENX320. See `CSI.ioctl`.
+   Automatically disables hot pixels — pixels that fire
+   spuriously even on a static scene. The driver builds a
+   320x320 per-pixel hit count, computes the mean and standard
+   deviation, and disables any pixel whose count exceeds
+   ``mean + sigma * stddev``. Pass an event-count budget
+   (events to tally before computing statistics — higher = more
+   reliable estimate, slower; ~10000 is a good default) and a
+   sigma float (lower = more aggressive, ~0.5 default). Returns
+   the number of pixels disabled. Aim the cam at a static scene
+   first so motion-driven events don't get counted against
+   pixels that are actually fine. See `CSI.ioctl`.
 
 .. data:: IOCTL_GENX320_READ_EVENTS_RAW
    :type: int
 
-   Returns a raw event-frame `image.Image` from the GENX320. See `CSI.ioctl`.
+   Returns a raw event-frame `image.Image` from the GENX320,
+   with the events still in the chip's native packed encoding —
+   useful if you want to forward the raw stream to a PC for
+   off-line decoding rather than process it on the cam. See
+   `CSI.ioctl`.
 
 .. data:: PIX_OFF_EVENT
    :type: int
 
-   Pixel-off event.
+   GENX320 event type (column ``[0]``) — a pixel detected a
+   brightness decrease (the negative-contrast threshold was
+   crossed). Columns ``[4]/[5]`` carry the pixel's X/Y.
 
 .. data:: PIX_ON_EVENT
    :type: int
 
-   Pixel-on event.
+   GENX320 event type (column ``[0]``) — a pixel detected a
+   brightness increase (the positive-contrast threshold was
+   crossed). Columns ``[4]/[5]`` carry the pixel's X/Y.
 
 .. data:: RST_TRIGGER_RISING
    :type: int
 
-   Pixel reset rising-edge event.
+   GENX320 event type (column ``[0]``) — pixel-reset trigger,
+   rising edge. X/Y are unused. Not generated by the firmware
+   at this time.
 
 .. data:: RST_TRIGGER_FALLING
    :type: int
 
-   Pixel reset falling-edge event.
+   GENX320 event type (column ``[0]``) — pixel-reset trigger,
+   falling edge. X/Y are unused. Not generated by the firmware
+   at this time.
 
 .. data:: EXT_TRIGGER_RISING
    :type: int
 
-   External trigger rising-edge event.
+   GENX320 event type (column ``[0]``) — the sensor's external
+   trigger pin saw a rising edge. The GENX320's external trigger
+   input is wired to the camera's frame-sync line, also routed
+   to **P10** on the processor and the pin header. X/Y are
+   unused.
 
 .. data:: EXT_TRIGGER_FALLING
    :type: int
 
-   External trigger falling-edge event.
+   GENX320 event type (column ``[0]``) — the sensor's external
+   trigger pin saw a falling edge. The GENX320's external trigger
+   input is wired to the camera's frame-sync line, also routed
+   to **P10** on the processor and the pin header. X/Y are
+   unused.