Using with Raspberry Pi

Required Hardware

Development Kits

AD-GMSLCAMRPI-ADP# GMSL EV Kit Adapter Board
MAX96724 GMSL Deserializer Evaluation Kit
MAX96717 GMSL Serializer Evaluation Kit or GMSL camera
Raspberry Pi 4 Model B (2GB of RAM or more preferred) or Raspberry Pi 5 (2GB of RAM or more preferred)

Supported Image Sensors & Cameras

Cables

Warning

Do not use the 15-pin ribbon cable included with the Raspberry Pi camera since that is an opposite sided cable.

Raspberry Pi 4:

15-Pin Type A (same side) Flexible Ribbon Cable, P/N: MP-FFCA10152003A or similar
22-Pin Type B (opposite side) Flexible Ribbon Cable, P/N: MP-FFCA05222002B or similar
FAKRA Jack to FAKRA Jack coaxial cable, provided in EV kits

https://media.githubusercontent.com/media/analogdevicesinc/documentation/main/docs/solutions/reference-designs/ad-gmslcamrpi-adp/raspberry-pi-user-guide/RPI4/adaptor_block_diagram.png — Figure 1 GMSL Signal Chain - Raspberry Pi 4

Raspberry Pi 5:

15-Pin Type A (same side) Flexible Ribbon Cable, P/N: MP-FFCA10152003A or similar
22-Pin Type B (opposite side) Flexible Ribbon Cable, P/N: MP-FFCA05222002B or similar
22-Pin Type A (same side) Flexible Ribbon Cable, P/N: MP-FFCA05222002A or similar
FAKRA Jack to FAKRA Jack coaxial cable, provided in EV kits

Board Modifications

Using the procedure to Set CFG Pin Levels, configure the SerDes pair as follows:

Pin	MAX96717	MAX96724
CFG0	0 – I2C, ROR, 0x80	0 – I2C, 0x4E
CFG1	7 – Coax, 6 Gbps, Pixel	0 – Coax, GMSL2, 6Gbps

Important

It is required to set the CFG pins to the indicated levels for this setup.

For more information about the default CFG configuration of each evaluation board, please visit the respective datasheet documentation:

GMSL Deserializer Evaluation Kit

Slide the SW5 switches to the ON position to enable I2C communication over the CSI bus
Remove the J18 and J19 jumpers to allow the RPi to become the Main host controller for the I2C lines
Make sure the J3 is set as default 2-3 position to enable POC

Figure 3 SW5 Switch for Enabling I2C
Bridge R88 - provides VDDIO to the adapter

Figure 4 R88 for VDDIO Provision

GMSL Serializer Evaluation Kit

Place a jumper on the J10 connector to enable power over the coaxial cable

Figure 5 J10 for Power over Coax
Bridge R70 - provides 12V to the adapter
Bridge R80 - connects MFP2 to the adapter for IMX219
Bridge R66 - provides VDDIO to the adapter

Figure 6 Serializer Resistors

AD-GMSLCAMRPI-ADP# Adapter

Configure the switch S2 on the GMSL Serializer adapter for CAM1 on connector P9
Configure the switch S1 on the GMSL Deserializer adapter for CAM2 on connector P6 and slide switch S3 towards connector P6

Serializer Adapter

Deserializer Adapter

System Setup

MAX96717 Serializer EV Kit Configuration

For the following setup, please ensure ribbon cables and boards are oriented to match the diagrams.

Connect the 15-pin ribbon cable to the camera board.

Connect the other end of the 15-pin ribbon cable into the 15- to 22-pin adapter board.

On the other side of the 15- to 22-pin adapter board, connect the 22-pin opposite-sided ribbon cable.

Connect the other end of the 22-pin opposite-sided ribbon cable into the EV Kit adapter board P9 connector.

Lastly, connect the EV kit adapter board to the MAX96717 EV Kit.

MAX96724 Deserializer EV Kit Configuration

Raspberry Pi 4

Starting with the Raspberry Pi 4B, connect the 15-pin ribbon cable to the CSI input connector.

Connect the other end of the 15-pin ribbon cable into the 15- to 22-pin adapter board.

On the other side of the 15-to-22 pin adapter board, connect the 22-pin opposite-sided ribbon cable.

Connect the other end of the 22-pin opposite-sided ribbon cable into the EV kit adapter board P6 connector.

Lastly, connect the EV kit adapter board to the MAX96724 EV kit.

With both sides of the SerDes devices connected up, the last step is to connect the two sides together with the coax cable. The MAX96717 serializer only has one connection. The MAX96724 deserializer has 4 inputs so connect the coax cable to link A (INA) on J7.

Connect power to the 12V barrel jack J1 of the MAX96724 deserializer. If utilizing the GMSL GUI, also connect the micro USB cable to J6 of the MAX96724 deserializer EV kit.

Raspberry Pi 5

Starting with the Raspberry Pi 5, connect the 22-pin same-sided ribbon cable to the CSI input connector on J3.

Connect the other end of the 22-pin same-sided ribbon cable into the EV kit adapter board P6 connector.

Lastly, connect the EV kit adapter board to the MAX96724 EV kit.

With both sides of the SerDes devices connected up, the last step is to connect the two sides together with the coax cable. The MAX96717 serializer only has one connection. The MAX96724 deserializer has 4 inputs so connect the coax cable to link A (INA) on J7.

Connect power to the 12V barrel jack J1 of the MAX96724 deserializer. If utilizing the GMSL GUI, also connect the micro USB cable to J6 of the MAX96724 deserializer EV kit.

Raspberry Pi Configuration

Connect the USB-C power supply to the Raspberry Pi connector
Connect the HDMI cable from the monitor to the Raspberry Pi micro HDMI connector
Write the Raspberry Pi latest SD card image on an 8 GB (or more) SD card
Plug the SD card into the Raspberry Pi SD card slot
Connect a USB mouse and keyboard to the Raspberry Pi (it is possible to use either a mouse & keyboard combo or a separate mouse and keyboard)

Running the Evaluation Application

Once Linux boots, you will see the Linux desktop on the HDMI monitor. Double-click the Home icon and navigate to the Workspace folder. Right-click inside this folder and select the Open Terminal Here option. Inside the terminal, type the following command and hit Enter:

~$

./video_cfg.sh

This script configures the Linux V4L2 (Video4Linux2) media pipeline for a GMSL multi-camera system on a Raspberry Pi:

#!/bin/bash

CAM_LIST="cam0"
CAM_MODEL="imx219"
PYV4L2_PATH="/home/analog/Workspace/pyv4l2"
DT_MODEL_PATH="/proc/device-tree/model"

if [[ $(cat $DT_MODEL_PATH | tr -d '\0') =~ "Raspberry Pi 4" ]]; then
   echo "Running on RPI4"
   RPI_MODEL="rpi4"
elif [[ $(cat $DT_MODEL_PATH | tr -d '\0') =~ "Raspberry Pi 5" ]]; then
   echo "Running on RPI5"
   RPI_MODEL="rpi5"
else
   echo "Unknown platform"
   exit 0
fi

$PYV4L2_PATH/utils/cam.py -c -p "$RPI_MODEL"-gmsl-"$CAM_MODEL":$CAM_LIST

The following variables can be changed (if needed) inside the script:

CAM_LIST (specifies the list of cameras in the setup):

cam0 (default)

cam0,cam1

cam0,cam1,cam2

cam0,cam1,cam2,cam3

cam1,cam2

cam0,cam3

CAM_MODEL (specifies the model of the camera):

imx219 (default)

ov5640

The model of the Raspberry Pi does not need to be explicitly specified because the script detects it automatically.

After the script is done running, click on Applications (found in the top left corner), which will open a dropdown list of items. From this list, select Multimedia and then Qt V4L2 test Utility in order to start the video capture application. After the application opens, press the green play button to start capturing video.

The capture window will look as shown below.

Note

Some displays may have vertical/horizontal lines. This is typically an artifact caused on HDMI monitors and unrelated to the evaluation setup.

Power-off Sequence

Open a terminal and type sudo poweroff. This will safely power off the Raspberry Pi and ensure that the SD card is properly unmounted
Remove the power supply from the Raspberry Pi
Remove the power supply from the MAX96724 EV kit

Getting the Software

The GMSL Linux kernel drivers, the complete Linux distributions for the supported processing platforms, and software user guides can be found on the Analog Devices GMSL GitHub repository.

Tips for Troubleshooting

There are a few key commands in the Linux environment that can help identify if the expected connections and communications have been made.

In the Linux environment, you can check to see if the RPi I2C is detecting the GMSL boards by sending an I2C detect command [1] as follows:

~$

sudo i2cdetect -y 10

The result should look as follows in the terminal, if using the IMX camera:

user@kuiper-gmsl:~$

sudo i2cdetect -y 10

[sudo] password for analog:

1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
                        -- -- -- -- -- -- -- --
UU -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- UU -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- 64 -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- --

Or, as follows, if using the Pcam camera:

user@kuiper-gmsl:~$

sudo i2cdetect -y 10

[sudo] password for analog:

1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
                        -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- UU -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- -- -- -- -- -- 3c -- -- --
40 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-- -- -- -- -- -- -- --

You can also confirm that the Video for Linux application is detecting the camera and GMSL devices by using the following command:

~$

v4l2-ctl --list-devices

Raspberry Pi 4

The response should look like the following:

~$

v4l2-ctl --list-devices

bcm2835-codec-decode (platform:bcm2835-codec):
    /dev/video10
    /dev/video11
    /dev/video12
    /dev/video18
    /dev/video31
    /dev/media2

bcm2835-isp (platform:bcm2835-isp):
    /dev/video13
    /dev/video14
    /dev/video15
    /dev/video16
    /dev/video20
    /dev/video21
    /dev/video22
    /dev/video23
    /dev/media1
    /dev/media3

unicam (platform:fe801000.csi):
    /dev/video0
    /dev/video1
    /dev/media4

rpivid (platform:rpivid):
    /dev/video19
    /dev/media0

Note

For Raspberry Pi 4, the key idea is to identify the unicam output, which corresponds to the Raspberry Pi camera setup.

Raspberry Pi 5

The response should look like the following:

~$

v4l2-ctl --list-devices

pispbe (platform:1000880000.pisp_be):

     /dev/video20
     /dev/video21
     /dev/video22
     /dev/video23
     /dev/video24
     /dev/video25
     /dev/video26
     /dev/video27
     /dev/video28
     /dev/video29
     /dev/video30
     /dev/video31
     /dev/video32
     /dev/video33
     /dev/video34
     /dev/video35
     /dev/media0
     /dev/media1

rp1-cfe (platform:1f00110000.csi):

     /dev/video0
     /dev/video1
     /dev/video2
     /dev/video3
     /dev/video4
     /dev/video5
     /dev/video6
     /dev/video7
     /dev/media3

rpi-hevc-dec (platform:rpi-hevc-dec):

     /dev/video19
     /dev/media2