Subject: ESP32-P4-MINI-A + EXT: I2C bus on GPIO7/8 shows no devices (no codec, no OV5647)
Hello Spotpear support,
I bought the ESP32-P4-MINI-A set (core board, EXT expansion board, OV5647 camera with the supplied cable). The core board is soldered to the EXT board. Order number: [please add]
Problem: I cannot get the camera to work. An I2C scan on GPIO7 (SDA) / GPIO8 (SCL), the default I2C pins from your wiki, finds no devices at all, neither at 100 kHz nor at 400 kHz. According to the wiki the onboard codec should answer at address 0x18, and the OV5647 should answer at 0x36. Neither shows up.
Setup details:
- Chip: ESP32-P4 rev 1.3
- Firmware: ESPHome 2026.9.1 (ESP-IDF 5.5.5)
- Wi-Fi via the ESP32-C6 on the EXT board works (SDIO), so the EXT board is powered and connected to the core
- Camera module is connected with the supplied flat cable
Questions:
1. Are GPIO7/GPIO8 the correct I2C pins for both the codec and the CSI camera (SCCB) on the EXT board?
2. Is there any enable signal or power switch that must be set before the I2C devices on the EXT board respond?
3. Could you share the schematic of the ESP32-P4-EXT board, or the board support package / demo code with the pin definitions for the camera?
Thank you very much for your help.
Best regards,
Andreas
