Several modules together¶
JP150PCB 1.3PCB 1.4Jan PřibyslavskýThis page does not apply to the product or PCB revision chosen in the header.
More than one JP150 can play in one system. Three ways exist, each with its own place on this site.
Audio over I2S¶
Feed the audio into the first module through I2S INPUT and forward it to the next module through I2S OUTPUT; the next module's I2S INPUT takes it, and so on. What the output carries is decided by the DSP program: the default program forwards the selected input, so a chain plays the same signal everywhere, and an own program can send a processed or a different signal down the chain (for example the subwoofer feed of a 2.1 system). PCB 1.4 has a second output, I2S OUTPUT AUX, driven by the DSP's second serial port, which an own program can use for a second chain or a different mix. Pinouts and the pin-order differences between the revisions are on Connectors and pinouts; the DSP side is on The starter project.
Clocking, channel mapping and synchronisation along the chain are decided in the DSP programs of the modules; the firmware does not configure them.
Audio over the network¶
Several modules on the same network each receive their own stream from the streaming apps (Wi-Fi setup); grouping and synchronisation are done by the apps and the Wi-Fi module, not by the firmware. The module's volume follows the app's volume during playback (Volume and encoder).
Two modules over Bluetooth¶
A pair of modules plays one phone's audio in sync as a True Wireless Stereo pair: the phone connects to the Primary, which forwards the audio to the Secondary. Both play the full stereo signal; a left/right split is made in the DSP program. The whole procedure is in the Bluetooth section.
Control¶
Every module has its own control interface over USB and UART1, and MuraLink connects to one module at a time; a host that controls several modules opens one connection per module. The UART SLAVE connector is provided for connecting another module.