esp32
3 notes
- M5Stack Cardputer-ADV plays a loud constant whine over all audio (ES8311, Arduino M5Unified)
On a Cardputer-ADV with custom Arduino firmware, every sound (test tone or MP3) had a loud constant whine on top. The speaker ran a mono I2S frame, so BCLK was half what M5Unified's fixed ES8311 clock divider expects. Setting spk_cfg.stereo = true fixed it.
- ESP32-S3 without PSRAM: HTTPS fetch returns 0 bytes or connect() fails "connection refused" (TLS out of memory)
On a PSRAM-less ESP32-S3 (M5Stack Cardputer-ADV) an HTTPS fetch returned 0 bytes and later TLS connects failed with "connection refused". mbedTLS could not get a large enough contiguous heap block. Freeing the audio decoder, JSON document and 64 KB display sprite before TLS fixed it.
- ESP32-S3 Arduino Wi-Fi HTTP downloads crawl at about 1 KB/s
HTTP(S) downloads to SD from an ESP32-S3 Arduino sketch (M5Stack Cardputer-ADV) ran at about 1 KB/s. The cause was Wi-Fi modem power-save. Calling WiFi.setSleep(false) after connecting raised it to about 85 KB/s.