ROCK Pi 4

INTRODUCTION
ROCK Pi 4 is a Rock chip RK3399 based Single Board Computer by Radxa. It can run android or some Linux distributions. ROCK Pi 4 is a six-core ARM processor, 64-bit dual channel 3200Mb/s LPDDR4, up to 4K at 60 HDMI, MIPI DSI, MIPI CSI, 3.5mm jack with mic, 802.11 ac Wi-Fi, Bluetooth 5.0, USB Port, GbE LAN, 40-pin color expansion header, RTC. Also, ROCK Pi 4 response USB PD and QC powering. ROCK Pi 4 comes in two models, Model A, and Model B, each model has 1GB, 2GB or 4GB ram options.

Processor

The Rock chip RK3399 System on a chip used in ROCK Pi 4 includes 64bits hexacore processor with dual 1.8GHz Cortex-72 and Qualcomm 1.4GHz Cortex-A53, Mali T860MP4 graphics processing unit (GPU) and Internal SRAM. It has a level 1 (L1) cache and a level 2 (L2). For level 1 cache, 48KB I cache and 32KB D cache is for each A72. 32KB I cache and 32KB D cache is for each A53. For level 2 cache, the 1024KB cache is for big cluster and the 512KB cache is for the little cluster.

Networking

On the ROCK Pi 4 Model A, B board, the Gigabit Ethernet port is provided. From the test result, we know that the bandwidth is at least 939Mbits/Sec. If you are interested in POE (Power over Ethernet), you should try it on the Pi 4 board.

Peripherals

The ROCK Pi 4 Model A and B have four USB-A connectors. One is for USB 3.0 OTG. One is for 3.0 HOST. And the others are for USB 2.0 HOST. The hardware switch for host/device switch may be useful when you use the USB 3.0 OTG connector. The ROCK Pi 4 may be operated with any generic USB computer keyboard and mouse. It may also be used with USB storage, USB to MIDI converters, and virtually any other device/component with USB capabilities.

The ROCK Pi 4 Model A and B are equipped with a standard 3.5mm jack. An audio lead is necessary to produce sound when there is not an HDMI cable. Audio can be played through speakers or headphones using the jack. This requires you to use the Desktop volume control for configuration.

MIPI Camera Interface

There is a wide range of camera applications in our lives. MIPI CSI 2 lane onboard support 800 MP camera via FPC connector.

MIPI Display Interface

The ROCK Pi 4 Model A and B are equipped with one HDMI connector and one MIPI DSI. As for HDMI, the maximum resolution is 4k@60Hz. Any HDMI monitor should work as a display for the Pi 4. As for MIPI DSI, it is designed for a raw LCD panel. HDMI and MIPI DSI can work at the same time.

TF Card Interface

The TF card can be used as a system storage or external storage. When it’s used as system storage, you had better choose the ones with storage space larger than 8GB. When it’s used as external storage, you can choose the ones with storage space up to 128GB. When the TF card is inserted into the TF card slot, the device will be automatically recognized by the system.

EMMC Socket on Board Interface Feature

The high-performance eMMC module is the best choice as the system storage for ROCK Pi 4. The EMMC module with 8GB/16GB/32GB/64GB/128GB is available.

HDMI Interface

The ROCK Pi 4 Model A and B are equipped with one HDMI connector and one MIPI DSI. As for HDMI, the maximum resolution is 4k@60Hz. Any HDMI monitor should work as a display for the Pi 4. As for MIPI DSI, it is designed for the raw LCD panel. HDMI and MIPI DSI can work at the same time.

General purpose input-output (GPIO) connector

ROCK Pi 4 has a 40-pin expansion header. Each pin is distinguished by color.

IO Voltage

RK3399 has three IO voltages, 1.8V/3.0V/3.3V. For ROCK Pi 4, below is the default voltage:

IO Performance

ROCK Pi comes with multiple storage options and providing superior read and write performance on external storage drives, allowing quicker read and write speeds. This improves workflow, copying, backups and overall file usage.
ROCK Pi also features one USB 3.0 host and one USB 3.0 OTG ports, each 5Gbps/s, working independently. The USB 3.0 OTG can work as a USB device such as Android ADB or USB gadgets. A hardware switch is provided to the OTG mode switch.

RTC Battery

ROCK Pi 4 reserve an RTC battery connector to keep time when shut down. The RTC function is provided by the RK808 PMIC. The RTC battery spec as below:

• Connector type: XH1.25mm
• Voltage: 3.0V
• Battery model: CR2032

SPI Flash

RK3399 can boot from SPI/SD card/EMMC, the SPI buses for booting is SPI1. On ROCK Pi 4 V1.3 and earlier, the design has included the SPI flash but it was not soldered. There are several reasons:

• The SPI is also exported to the 40PIN GPIO header if we use it as boot ROM, then we will not able to use the SPI bus on the GPIO header
• If the boot loader in the SPI flash corrupted, it will brick the ROCK Pi 4, which is hardware for the normal user to recover.
• The boot loader doesn’t support booting from USB3 or NV Me before and there are tools missing to write to SPI flash easily.

Some advanced users may want to solder the SPI flash by themselves. The footprint for the SPI flash is SOP8, the voltage level is 3.3V. The size should be larger than 4MB (32Mbit) to store the boot loader. The verified working models are:

• W25Q64FV
• GD25Q127CSIG
• XT25F32B

AI Capabilities

ROCK Pi supports mainstream AI stack with GPU acceleration. Furthermore, a dedicated hardware NPU accelerator coming up next for ROCK Pi will boost a complex Machine Learning algorithm and reduce the power.
Industrial standard MIPI CSI connector makes it easy to connect existing cameras to ROCK Pi and ROCK Pi also supports the industrial standard MIPI DSI for LCD and touch screen. With hardware accelerated algorithm, it’s great for Computer Vision application, Robotics and much more.

Maker Friendly, IoT Connectivity

ROCK Pi features maker-friendly expansion options, including a 40-pin GPIO interface that allows for interfacing with range inputs from buttons, switches, sensors, LEDs, and much more.
ROCK Pi also features a Gigabit LAN for a network, with dedicated bus and controller, it works without latency under heavy load network applications. On board 802.11 Ac Wi-Fi offers 2.4G&5G WLAN connectivity. With Bluetooth 5.0, ROCK Pi benefits improved Bluetooth speed and greater range.