Homepage widgets

The homepage gauges (connection, OS, caps/num/win lock, battery) are drawn by the display module but fed by the keyboard as 1-byte PK_* status packets. This page is the firmware side; the packet format lives on Display commit (PK_*).

🔧 Boot handshake

b75Pro keyboard_screen.c runs a screen_boot_step state machine: on boot it pings PK_CONN_TYPE while the screen powers up, then pushes the whole widget batch to init the homepage.

Battery is part of the batch

The battery gauge is init'd as part of that batch — a lone PK_BATT_QUANTITY may have no widget to fill. This is why the gauge went empty on custom after the first image push: the module kept stock's widget state until the push cleared it, and the passthrough never re-inits.

⚙️ The port (v16)

AL80_CUSTOM_QMK_v16_homepage.bin ports this: al80_homepage_init() sends the batch on boot (4× over ~6 s) + every 30 s (self-heal) + battery every 10 s. It REPLACES v15's lone-battery push. UNTESTED on-device. VREF_CAL=1489 (12-bit) is calibratable; charge-status is hardcoded 0.

🔋 Battery read

ADC1 ch9 (PB1) + internal Vref ch17, mv = adc*1764/vref, piecewise thresholds 3200 mV (empty) … 4150 mV (full). Median-of-10 sampling (drop min/max, average the middle 8), 10-bit, piecewise-linear %. Source: b75Pro smart_ble.c / battery.c / adc.c (strings match the AL80 binary). See Hardware.