Deaf_Transcription_Service/docs/hardware-wiring.md

Hardware Wiring

Waveshare 7.5" V2 e-ink → ESP32

Display pin	ESP32 GPIO	Notes
BUSY	4	Input — display signals when busy
RST	16	Reset
DC	17	Data/command select
CS	5	SPI chip select
CLK	18	SPI clock (hardware SPI)
DIN	23	SPI MOSI
GND	GND
VCC	3.3 V	Do not use 5 V

These pin assignments match main.cpp. If you need to remap them, change the PIN_* defines at the top of the file — the SPI CLK and DIN pins (18, 23) are hardware SPI and cannot be freely remapped without switching to software SPI.

Power

• Display: powered from the ESP32 3.3 V rail. Current draw during refresh is ~30 mA peak — within ESP32 rail limits for a single display.
• ESP32: power from USB (5 V). For permanent installation use a 5 V USB wall adapter rated ≥ 1 A.

Audio input

Source	Connection	Notes
Mixing desk	Line-out → USB audio interface → PC USB	Cleanest signal; recommended
Microphone	USB condenser → PC USB	Use if mixer feed not available

Whisper performs best with a clean, low-noise signal. A direct line feed from the mixing desk eliminates room echo and background noise.