Host initdump proved mipidsi's MADCTL (0x48), COLMOD, and address window
(CASET 0..319 / RASET 0..479) already match CircuitPython exactly — so the 1/4
+ rotation wasn't an addressing bug. The missing piece was the ST7796 extension
init (B6/power/gamma) running as the PRIMARY bring-up right after reset (grafting
it onto mipidsi's already-DISPON'd panel blanked or under-configured it).
Now: manual hw reset + full CircuitPython st7796_init via the raw interface, THEN
Builder without reset_pin (re-asserts only the basics, extension setup persists).
initdump extended to also dump CASET/RASET draw windows.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Host initdump (rust/uisim --bin initdump) showed mipidsi emits only SLPOUT,
MADCTL=0x48, INVON, COLMOD, NORON, DISPON — MADCTL already matches CircuitPython,
but the ST7796 extension setup (unlock, 0xB6 480-lines, power, gamma) is missing,
and sending it AFTER mipidsi's DISPON blanked the live panel. Replay the full
known-good st7796_init via Display::dcs() ending in its own DISPON. Adds the
initdump tool (capture init byte sequence on the host, no bench).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
