This repo contains Information about connecting I2S DACs to ESP32 Boards and run snapclient https://github.com/CarlosDerSeher/snapclient on the Board.
The PCM5102A is available on small PCBs (branded as GY PCM5102A) with a 3,5mm jack for connecting an Amplifier. For the connection to the ESP32 the pins BCK, DIN and LCK/LRCK are necessary. XSMT/3 can optionally be used if Hardware Mute/Unmute is used. You can find some Solderpads on the PCB which should not be left floating for stable operation. This can also be realized by using a pin header and jumpers on the coresponding row of solderpads on the board.
- Short the solder jumper located between SCK and BCK on the front side of the PCB to pull SCK low
- H-3 L (leave open if Hardware Mute is used, or pull up, i.e. connect middle pad to H to enable audio output permanently)
- H 2-L (pull down, i.e. connect middle pad to L)
- H 1-L (pull down, i.e. connect middle pad to L)
- H-4 L (pull up, i.e. connect middle pad to H)
When using the Ethernetport of the Board only a limited set of the IO Pins are available. The following configuration works with Hardware Mute
| Olimex ESP32-PoE board pad | ESP32 GPIO | PCM5102A | Function |
|---|---|---|---|
| 13 | 13 | BCK | Clock |
| 14 | 14 | LCK/LRCK | Channel Select |
| 32 | 32 | DIN | Data |
| 33 | 33 | 3/XSMT | Hardware Mute |
This corresponds to the following settings in the snapclients esp-idf menuconfig tool:
- Audio Board -> Audio Board -> Custom audio board
- Audio Board -> Custom Audio Board -> DAC Chip -> TI PCM5102A based DAC
- Audio Board -> Custom Audio Board -> DAC I2C control interface:
Value Description -1 SDA Pin -1 SCK Pin 0x20 I2C address - Audio Board -> Custom Audio Board -> I2S Master Interface:
Value Description -1 Master i2s mclk 13 Master i2s bck 14 Master lrck 32 Master i2s data out - Audio Board -> Custom Audio Board -> TI PCM5102A interface Configuration:
Value Description 33 Master mute/unmute for PCM5102A - Audio Board -> Custom Audio Board -> Logic-Level-Settings -> leave all unchecked
- Snapclient Ethernet Configuration
Value Description checked Internal EMAC LAN87xx Ethernet PHY Device 23 SMI MDC GPIO number 18 SMI MDIO GPIO number 16 PHY Reset GPIO number 0 PHY Address unchecked SPI Ethernet
The externally accessible GPIO pins on this board have several pecularities. See the very useful repo Unofficial guide to the WT32-ETH01 for reference. The following GPIO selection has proven to be working fine:
| WT32-ETH01 board pad | ESP32 GPIO | PCM5102A | Function |
|---|---|---|---|
| CFG | 32 | BCK | Clock |
| RXD | 5 | LCK/LRCK | Channel Select |
| 485_EN | 33 | DIN | Data |
| IO15 | 15 | 3/XSMT | Hardware Mute |
This corresponds to the following settings in the snapclients esp-idf menuconfig tool:
- Audio Board -> Audio Board -> Custom audio board
- Audio Board -> Custom Audio Board -> DAC Chip -> TI PCM5102A based DAC
- Audio Board -> Custom Audio Board -> DAC I2C control interface:
Value Description -1 SDA Pin -1 SCK Pin 0x20 I2C address - Audio Board -> Custom Audio Board -> I2S Master Interface:
Value Description -1 Master i2s mclk 32 Master i2s bck 5 Master lrck 33 Master i2s data out - Audio Board -> Custom Audio Board -> TI PCM5102A interface Configuration:
Value Description 15 Master mute/unmute for PCM5102A - Audio Board -> Custom Audio Board -> Logic-Level-Settings -> leave all unchecked
- Snapclient Ethernet Configuration
Value Description checked Internal EMAC LAN87xx Ethernet PHY Device 23 SMI MDC GPIO number 18 SMI MDIO GPIO number 16 PHY Reset GPIO number 1 PHY Address unchecked SPI Ethernet