Sync Stereo Camera HAT User Manual

1. Introduction

Now Arducam released a stereo camera HAT for Raspberry Pi which allows you to connect two 5MP OV5647 or two 8MP IMX219 pi cameras to a single standard pi board, and takes images or video at the same time, even more, important they are fully synchronized.

The highlight of this stereo camera HAT is that it incorporates Arducam proprietary ArduChip solution, and extends the usage of the single pi camera port, it cheats the Raspberry pi as if only one camera connected. It supports Raspistill command for preview and Raspivid command for video capture/processing with Rpi default camera driver for its 5MP and 8MP cameras.

It also supports other Arducam Raspberry Pi cameras and a proprietary camera driver that works up to two 16MP. With the shared oscillator and I2C broadcasting, the two cameras are fully synchronized in the nano-second level. With the latest new coming Pi 4 hardware, Arducam makes more camera applications possible for Raspberry Pi.

2. Features & Key Specifications

• Support all series Raspberry Pi boards, Pi HAT board style
• Two MIPI camera inputs and one MIPI camera output
• Support 1, 2 and 4 lane MIPI cameras input up-to 800Mbps/lane
• Support 2 lane MIPI output
• Support Raspistill (preview) and Raspivid (processing) commands for 5MP/8MP pi cameras with half-resolution combine
• Support Arducam RPI cameras up to 16MP with proprietary camera driver with full resolution combine
• Support camera side-by-side combine, channel 0 and channel 1 software switching on the fly
• Support digital pan in half resolution combine, programmable pan speed control
• Board size: 65 x 56 mm
• Weight: 16 g
• Contact us for other platform support

2.1 Framerate

2.1.1 Stereo 5MP OV5647

mode: 5, width: 5184, height: 1944, 12fps
mode: 6, width: 3840, height: 1080, 22fps
mode: 7, width: 2592, height: 972, 33fps
mode: 8, width: 2560, height: 720, 12fps
mode: 9, width: 2592, height: 730, 33fps
mode: 10, width: 1280, height: 480, 45fps

2.1.2 Stereo 8MP IMX219

mode: 7, width: 1600, height: 600, 22fps
mode: 8, width: 2560, height: 720, 38fps
mode: 9, width: 3840, height: 1080, 18fps
mode: 10, width: 5184, height: 1944, 9fps
mode: 11, width: 6528, height: 1848, 12fps
mode: 12, width: 6528, height: 2464, 4fps

3. Applications

• Stereo Vision
• 360 Camera
• Advanced Surveillance Camera

4. Assembly Instruction

4.1 Step 1

You need to modify your current Raspberry Pi V1.3 or V2 camera board with a soldering iron and hot air gun. This step can be skipped if you are using Arducam 5MP or 8MP stereo camera board like the Figure2 shows.

For 8MP V2 Pi Camera

Removing the resistor and crypto IC marked in a circle from one of the camera board and using jumping wires soldered to the pads as shown in Figure 3, twist the jumping wires will improve the signal quality.

For 5MP V1.3 Pi Camera

Removing the oscillator IC marked in a circle from one of the camera board and using jumping wires soldered to the pads as shown in Figure 4, twist the jumping wires will improve the signal quality.

For OV9281 1MP Global Shutter camera

Removing the oscillator IC marked in a square from one of the camera board and using jumping wires soldered to the pads as shown in Figure 4.1, twist the jumping wires will improve the signal quality.

For 16MP IMX298 Camera

4.2 Step 2

Attach the 22pin-15pin ribbon cable to the stereo camera HAT (22pin end) and Raspberry Pi CSI port (15pin end).

4.3 Step 3

Plug the stereo camera HAT on top of the Raspberry Pi, align the HAT Pin1 to RPI’s Pin1, then using the screws to fasten the HAT.

4.4 STEP 4

Attach the two camera 22pin ribbon cable to the stereo camera HAT.

5. Quick Start Guide

5.1 Activate the I2C bus

If you are using a 5MP Camera, you need to activate the I2C bus first, then run an additional script to ensure that the stereo camera runs for a long time.

Launch the terminal window and run the following commands,

sudo nano /boot/config.txt

Add the following statement to the configuration file,

dtparam=i2c_vc=on

Then input Ctrl+X，Y，Enter to save and exit the file.

Note: You only need to enable the I2C bus once.

5.2 Using Raspistill Command

Run the following command from the terminal window to preview two camera feed at the same time.

raspistill -t 0 -p 800,100,1024,768

If the 5MP Camera is used, launch another terminal window to run the following commands (Not required for 8MP camera).

i2cset -y 0 0x36 0x48 0x0400 w

5.3 Using Raspivid Command

Run the following command from the terminal window,

raspivid -p 800,100,1024,768 -o video.h264 -t 20000

If the 5MP Camera is used, launch another terminal window to run the following commands(Not required for 8MP camera).

i2cset -y 0 0x36 0x48 0x0400 w

Then playback the recorded .h264 video file from the VLC player or similar.

5.4 Advanced Controls

The stereo camera HAT support channel selection and digital pan. It requires to write onboard ArduChip registers through the I2C bus on Raspberry Pi. So the user needs to active the I2C bus first(please refer to chapter 5.1 or the following methods).

Clone the GitHub repository from https://github.com/ArduCAM/MIPI_Camera.git and run the script ./enable_i2c_vc.sh, a reboot is required.

For more information about the ArduChip registers, please refer to chapter 7.

Before issuing any control command, you have to launch preview or video using raspistill or raspivid command first, then launch another terminal window to run the following commands.

5.4.1 Switch to CAM0, Single Mode

Run command i2cset -y 0 0x24 0x24 0x01 to switch from stereo mode to single mode CAM0 feed.

5.4.2 Switch to CAM1, Single Mode

Run command i2cset -y 0 0x24 0x24 0x02 to switch from stereo mode to single mode CAM1 feed.

5.4.3 Digital Pan Mode

Run command i2cset -y 0 0x24 0x24 0x02 to switch to digital pan mode, each camera feed will pan back and forth to get an entire field of view of the camera.

Run the command i2cset -y 0 0x24 0x25 0x20 to change the pan speed, the speed value 0x20 can be modified from 0x01～0x60.

5.4.4 Full Combine Mode

Full resolution combine mode doesn’t work with raspistill and raspivid mode, it requires Arducam MIPI camera driver from GitHub: https://github.com/ArduCAM/MIPI_Camera/tree/master

launch the terminal window to run the following commands.

a) Download and install the SDK library

git clone https://github.com/ArduCAM/MIPI_Camera.git

cd MIPI_Camera/RPI/
make install 

b) Compile the Examples

make clean && make

c) Run the Examples

The list_format command is used to check all resolution the sensor you are using supports.

./list_format 

The mode containing Used for Arducam Synchronized stereo camera HAT in the prompt can support Full Combine Mode.

Select mode 5 as an example,

./arducamstill -t 0 -m 5

6. Pin Definition

Table 1 MIPI CAM 0 and MIPI CAM 1 Input Ports

Table 2 MIPI Camera Output to Raspberry Pi CSI Port

Table 3 2×3 Pin Header Port to Raspberry Pi

7. ArduChip Registers

ArduChip is the Arducam proprietary solution to control all the hardware internal logic to do the image capture and merge timing controls. There are set of register which allow users to switch to different mode according to their application. The stereo camera HAT acts like a standard I2C slave device, its registers are accessed from the Raspberry Pi Camera CSI port with I2C-0 bus and default 7-bit I2C slave address is 0x24.

Table 4 Stereo Camera HAT Register Table

8. Mechanical Dimension

Figure 12 Mechanical Drawing