Sonoff NSPanel Pro 120: Sound [Part 2]

This part will focus on getting the capture device to work. In our case, it involves two PDM digital microphones. PDM MICs A PDM (Pulse Density Modulation) microphone is a type of digital microphone that converts analog sound waves into a digital signal using a technique called Pulse Density Modulation.

Sonoff NSPanel Pro 120: Sound [Part 1]

Let's look at simplified Linux Audio stack: ALSA (Advanced Linux Sound Architecture) is a core component of the Linux kernel, providing audio and MIDI functionality. It manages communication between sound hardware (e.g., sound cards or onboard chips) and software applications. In Linux, there are two types of

Sonoff NSPanel Pro 120: GPU

The RK3326 chip includes a Mali-G31 GPU that supports: * DirectX 11 (FL 9_3) * OpenGL ES 1.1, 2.0, and 3.2 * Vulkan 1.0 * OpenCL 2.0 Full Profile This enables efficient 3D graphics and compute capabilities for gaming, rendering, and GPGPU tasks. The RK3326 chip is widely

Sonoff NSPanel Pro 120: WiFi/BT [Part 2]

In the previous article, we got the Wi-Fi working and tested. Since the module is a combo Wi-Fi/BT, Bluetooth is part of the same chip. It's time to get Bluetooth up and running. Bluetooth In Linux, BlueZ is the official Bluetooth protocol stack. It allows different Bluetooth

Sonoff NSPanel Pro 120: WiFi/BT [Part 1]

In previous articles, we already identified that the WiFi/BT combo chip used is the RTL8723DS. This chip supports Wi-Fi 2.4GHz (802.11b/g/n) and Bluetooth 2.1/4.2. While it doesn’t offer the best performance available on the market, it is still a solid and

Sonoff NSPanel Pro 120: Touch Panel

In this post, let's get the touchscreen working. But first, let's review the extracted .dts file to see what devices are connected to the i2c1 bus. i2c @ff190000 { compatible = "rockchip,rk3399-i2c"; reg = < 0x00 0xff190000 0x00 0x1000 > ; clocks = < 0x02 0x1e 0x02 0x14f

Sonoff NSPanel Pro 120: Linux Display Subsystem [Part 2]

In the previous article, we found out what the DSS (Display Subsystem) consists of and its terminology. We also have a .dts reference file from the factory firmware, so we are ready to define our peripheral in the DTS and finally make the screen work. Let’s create a new

Sonoff NSPanel Pro 120: Building And Running Linux

So, assuming we’ve already synced the RK3326 Linux SDK and are familiar with how Linux is booted, in this article, let’s compile a new Linux firmware and upload it to the device. The Rockchip Linux SDK provides three rootfs options: Buildroot , Debian , and Yocto . I’ll choose Buildroot

Sonoff NSPanel Pro 120: Linux Display Subsystem [Part 1]

The first thing we would like to get working in our fresh Linux build is, of course, the LCD screen, as it is essential for running any kind of desktop environment. The graphics stack on Linux can be a bit complicated. The following diagram illustrates the full relationship between the

Rockchip RK3326 Linux SDK: Boot Flow Overview

In this article, let's focus on the boot sequence of Rockchip SoCs running Linux and try to understand the terminology, what each component is, and what it is responsible for. So, let's start with the simplified feature image above. BootROM (aka Boot Code) This is the

Sonoff NSPanel Pro 120: Loader and Maskrom mode

MaskROM and Loader mode are special Rockchip modes that allow a user to read/write data to memory using USB. MaskROM is internal firmware that runs on the Rockchip SoC when no bootable device is found or when a special pin is tied to ground. Since MaskROM is built into

FTDI FT232RL: Bit Bang Mode (Linux) [Part 2]

In the previous post, we covered the installation of FTDI drivers on Ubuntu. This section focuses on controlling GPIO using a Python script. FTDI has 8 digital pins used for serial connections (RXD, TXD, RTS, CTS, DTR, DSR, DCD, RI) and 5 CBUS pins. Initially, I thought to use the