RLINK is a long-distance wireless data link communication module developed by blicube.LLC, supporting Point to Point and Point to Multipoint. Using two RLINK modules to form a pair of data links for mutual communication, when one connected to the device end and the other connected to the computer end. With three or more RLINK modules, it can be used for Point to Multipoint.
Based on bulid-in P900 module, RLINK has the characteristics of high transmission power, high link rate, high receiving sensitivity, etc. The ground-to-air communication distance is up to 60KM, the transmitting power can reach 1W, besides the module supports wide voltage input (5～35V) and high-speed frequency hopping. The module has the operating temperature range of -40 to 80 degrees, with shell of CNC aviation aluminum alloy materials.
The module size is shown in Figure 1.2. The mounting hole is a through hole with a diameter of 3.2, which is suitable for M3 bolt.
Figure 1.2 The physical dimension of RLINK
Use Guide
Interface
The RLINK module has two GH1.25 interfaces, shown in Figure 2 .1, where the left side is the power supply interface, which is recommended to use the provided circuit board for power supply, and the right side is a serial interface.
Figure 2.1 The interfaces of RLINK
Default Parameter
RLINK has been configured when you get it. The default link rate is 230 kbps, the boud rate of serial interface is 57600, and the default broadcast mode is Point to Point. If you want to modify the relevant parameters, please refer to Part 3 for custom configurations.
Since output power is up to 1W, some controller’s and computer’s interfaces have not the ability to supply such high power, it is recommended strongly that using a separate battery to supply power for RLINK for the stability.
Ground Station
Connect RLINK(the ground end) to computer as a monitor via a data cable, it can be auto connected when using QGroundControl. While when using Mission Planner as your ground station, it is necessary to select communication port and baud rate as shown in figure 2.2 at first, click CONNECT and then wait for the connection to complete.
Figure 2.2 Settings in Mission Planner for RLINK
Configuration
RLINK has been configured at the factory and generally does not require additional configuration. If you need to modify the parameters, you can customize the configuration according to the instructions below.
Enter Configuration Mode
Connect RLINK(the ground end) to the computer via a data cable at first, make sure the your serial assistant can communicate with RLINK, press and hold the RLINK CONFIG key with a thimble or other sharp object. The RLINK will enter configuration mode when the serial assistant pops up the NO CARRIER 0K prompt and then release CONFIG key.
Figure 3.1 Enter configuration mode
After entering configuration mode, the configuration can be completed by sending the relevant parameters via the serial assistant (all with OK after successful configuration). Noting that every configuration command needs to be followed by a carriage return.
AT&F10: Master of Point to Point
AT&F11: Slave of Point to Point
AT&F12: Repeater of Point to Point
AT&F7: Master of Point to Multipoint
AT&F8: Slave of Point to Multipoint
AT&F9: Repeater of Point to Multipoint
Point to Point Configuration
Please copy the reference commands to the serial assistant, press enter and then click Send, and the configuration is successful with OK:
Master (ground end) parameter settings：
Note：
ATS105: 1;
ATS140: from 2 to 65535.
Example:
Set to Master mode, Baud rate of 57600, Link rate of 230400, Network address 1234567890, Output power 100mW, Unit address 1, Destination address 2.
Point to Mutlipoint configuration is complex, if required, please contact customer service for configuration.
Precautions
RLINK has been configured to be ready to use, if you modify the parameters of RLINK that cannot be used normally, please contact customer service.
This product is a wireless digital transmission link, suitable for unobstructed environment, stable communication distance by the impact of the actual application site.
RLINK has a maximum power of 5W, and if your computer or RLINK is not working properly, check the RLINK power supply.
Remote RLINK and ground-end RLINK can be used interchangeably if used in Point to Point mode, and not interchangeable in Point to Mutlipoint mode.
This module takes the incoming HDMI signal and converts it into a separate CSI signal and I2S audio signal. HDMI input supports up to 1080P60Hz. It works well on raspberry pi, there are three versions of this module in history(C779、C780、C790). C790 is the latest version. C790 has mitigate HDMI backpowering,also has two csi channels and four csi channels at the same time.
Features
C790
hardware parameters
HDMI input: supports up to 1080P60Hz on Raspberry Pi
HDMI to CSI-2 bridge chip:Toshiba TC358743XBG
4 CSI-2 channels & clock
The CSI-2 interface, with 15 pin FPC seat, spacing 1.0 mm, is located on the front of the C790 module.
The CSI-2 interface, with 22 pin FPC seat, spacing 0.5 mm, is located on the back of the C790 module.
Size: 30 x 45 mm
Install:4 x M2.5
Power supply:3.3V
Weight: 10g
interface
C790 has two csi output interface. In fornt of C790, the CSI-2 interface is 15 pin FPC seat, spacing 1.0 mm. In back of C790, the CSI-2 interface is 22 pin FPC seat, spacing 0.5 mm.
size
C780
hardware parameters
C780A
HDMI input: supports up to 1080P50Hz on raspberry pi(Limited by the number of CSI-2 channels)
HDMI to CSI-2 bridge chip:Toshiba TC358743XBG
2 CSI-2 channels & clock
CSI-2 interface: 15 pin FPC seat, spacing 1.0 mm
Size: 30 x 65 mm (unbroken PCB size); 30 x 45 mm (PCB size after breaking)
Install:6 x M2.5
Power supply:3.3V
Weight: 9g
C780B
HDMI input: supports up to 1080P60Hz on raspberry pi
HDMI to CSI-2 bridge chip:Toshiba TC358743XBG
4 CSI-2 channels & clock
CSI-2 interface: 22 pin FPC seat, spacing 0.5 mm
Size: 30 x 65 mm (unbroken PCB size); 30 x 45 mm (PCB size after breaking)
Install:6 x M2.5
Power supply:3.3V
Weight: 9g
interface
The wiring of audio part is shown in Figure.
size
The size of C780 is shown in Figure. There are 6 mounting holes with a diameter of 2.75mm, which are suitable for M2.5 screws.
As shown in Figure, the user can directly fix the module on the raspberry pi zero.C780 is designed to be broken, and the hole spacing before breaking can be perfectly installed with most series of raspberry pi.
C779
Software demo
The use guide of C790/C780/C779 depends on the official Raspberry Pi OS version you are using. Different versions have different usage methods. If you have some questions, Join our BLIKVM Discord Community for Support, FAQ & News!
To use the kernel drivers, please update your system. There are a few things that have changed with the 5.4 kernel, so these instructions are for 5.4 or later. If “uname -a” reports anything less, then fix this before proceeding.
pi@raspberrypi:~ $ uname -a
Linux raspberrypi 5.10.63-v7l+ #1459 SMP Wed Oct 6 16:41:57 BST 2021 armv7l GNU/Linux
1. Update & upgrade the raspberry pi system (It will take a long time depend on the different country)
sudo apt-get update
sudo apt-get upgrade
2. Enable camera module (the camera is enabled by default in Raspberry pi Bullseys OS)
sudo raspi-config
sudo reboot
Navigate to ‘Interfacing Options’ and hit Enter. Now select the ‘Camera’ option, and hit the Enter key to enable it. Select “Finish” and select to reboot your Raspberry Pi.
[NOTE] reboot is important!!
3. Edit /boot/config.txt (that will need sudo)
sudo nano /boot/config.txt
Add the line:
dtoverlay=tc358743
Add the line if your shield support audio like C780 or C790
dtoverlay=tc358743-audio
please append the If (and only if) you have a device such as the C780 or C790 that supports the 22pin connector with all 4 lanes wired out, and are using a Compute Module with the CAM1 connector that also has all 4 lanes wired up, you can use
dtoverlay=tc358743,4lane=1
4. Check the amount of memory assigned to the CMA heap with “dmesg | grep cma”. The first line should be along the lines of
If it reports less than 96MB assigned to CMA, then edit /boot/cmdline.txt and add
cma=96M
to the start of the line. Do NOT add any carriage returns.
5. Reboot. If all is well you should get a /dev/video0 device, and “v4l2-ctl –list-devices” will tell you that it is provided by Unicam. After connecting all the cables, power on the Raspberry Pi, the C790 indicator light is normally green, and after opening the Raspberry Pi terminal, enter the following command:
6. This driver puts all the control in the hands of the user, or the user’s application. By default there is no EDID loaded into the chip to allow it to tell the HDMI source what resolutions are supported. There are EDID editors around. If you create a file edid.txt, then you can push this to the device using
cd ~
sudo nano edid.txt
#copy the above commend in edid.txt, save&exit;
pi@raspberrypi:~ $ v4l2-ctl --set-edid=file=edid.txt --fix-edid-checksums
CTA-861 Header
IT Formats Underscanned: yes
Audio: yes
YCbCr 4:4:4: no
YCbCr 4:2:2: no
HDMI Vendor-Specific Data Block
Physical Address: 3.0.0.0
YCbCr 4:4:4 Deep Color: no
30-bit: no
36-bit: no
48-bit: no
CTA-861 Video Capability Descriptor
RGB Quantization Range: yes
YCC Quantization Range: no
PT: Supports both over- and underscan
IT: Supports both over- and underscan
CE: Supports both over- and underscan
7. The driver does NOT automatically switch to the resolution detected. Use the command:
pi@raspberrypi:~ $ v4l2-ctl --query-dv-timings
Active width: 1280
Active height: 720
Total width: 1650
Total height: 750
Frame format: progressive
Polarities: -vsync -hsync
Pixelclock: 74250000 Hz (60.00 frames per second)
Horizontal frontporch: 0
Horizontal sync: 370
Horizontal backporch: 0
Vertical frontporch: 0
Vertical sync: 30
Vertical backporch: 0
Standards:
Flags:
You MUST set the timings via “v4l2-ctl –set-dv-bt-timings”. You can pass in an index to the detected mode, or use:
v4l2-ctl --set-dv-bt-timings query
to select the currently detected timings.
v4l2-ctl -V
should now reflect the resolution detected.
8. The chip supports two formats – BGR3 (the default) and UYVY. BGR3 is 24bpp, and UYVY is YUV4:2:2 16bpp.
Over the normal 2 CSI-2 lanes the data rate is such that BGR3 can run at a maximum of 1080p30, whilst UYVY will go up to 1080p50. Use the following command to select UYVY, however your application may override that.
v4l2-ctl -v pixelformat=UYVY
9. Check that the audio drivers / card is available to ALSA.
If your gstreamer is version 1.8 or above, you can try the following test command. In addition, alsasrc device=hw:1 represents the sound card of TC358743, you can use “arecord -l” to query.
#The sample command to recode a video without audio. (C779 doesn't support audio)
gst-launch-1.0 -vvv v4l2src ! "video/x-raw,framerate=30/1,format=UYVY" ! v4l2h264enc extra-controls="controls,h264_profile=4,h264_level=13,video_bitrate=256000;" ! "video/x-h264,profile=high, level=(string)4.2" ! h264parse ! queue ! matroskamux name=mux ! filesink location=foo.mkv
Press CTRL+C to end recording.
PS: We recommend that you modify the above framerate parameter to the actual frame rate of your HDMI signal, the actual frame rate value is from the result of ‘v4l2-ctl –query-dv-timings’ command.
For the above HDMI device, because the frame rate is 60, so we modify the framerate parameter to 60 like the followint command.
Note: alsasrc device=hw:1 – “1” means the audio card number, You must change to correct audio card number.(Query the car number via ‘arecord –l’, refer to step 9)
12. For old raspberry pi os, you can use Raspistil to take photo.
GRTK is a dual-antenna high-precision differential positioning and directional module (Real Time Kinematics) independently developed by Blicube. A complete RTK system can be formed through two GRTK modules (one mobile terminal and one base station terminal).
The module is based on a new generation of high-performance GNSS SoC chip design,supports multi-system multi-frequency RTK positioning, supports dual-antenna high-precision orientation, and supports GPS&GLONASS&Beidou&Galileo&QZSS navigation and positioning. It is mainly for high-precision positioning and orientation requirements such as drones, robots and intelligent driving.
Figure 1.1 Physical image of GRTK centimeter-level positioning and orientation system
< 5% of distance travelled during GPS denied conditions
Working Temperature
-20℃ to +85℃
Power Supply
5v to 35v
Physical size
Figure 1.2 Schematic diagram of physical size
Usage
Interfaces
The GRTK module can be used as a base station or as a mobile station. There are three interfaces in total, as shown in Figure 2.1. They are the Power port for powering the device, the com1 port for communication between the mobile station and the base station, and the com2 port for communicating with the flight controller to transmit positioning information. The com2 port includes uart2 and uart3, and the default use of uart2 is the serial port of flight control communication.
Figure 2.1 GRTK module interfaces diagram
In addition, there are four LED indicators on the front of the module. The three on the left display the module’s operating status, which are 3D Fix positioning status, operating error, and RTK positioning status; a single indicator on the right is used to display the power supply status.
The GRTK module supports dual antenna direction finding, where the left antenna(ANT1) is the master antenna, the right antenna(ANT2) is the slave antenna, and the single antenna needs to be connected to the master antenna.
Hardware connection
Base station connection
Figure 2.2 Base station connection diagram
Figure 2.3 Schematic diagram of base station tripod installation
Rover connection
Figure 2.4 Rover connection diagram
Dual-antenna rover connection
Figure 2.5 Dual antenna rover connection diagram
When the base station is not used, only the rover can be used as a conventional positioning device for positioning. The connection is shown in Figure 2.3.
The base station and the rover can be used together to form an RTK centimeter-level positioning system, and the base station supports plug and play.
The dual-antenna direction finding of the rover needs to keep the master-slave antenna consistent with the heading in accordance with the master-back-and-forward. The distance between the master-slave antennas should be greater than 30cm to ensure the direction finding accuracy.
Indicator light & Positioning status
There are 4 indicators on the GRTK module, the specific meanings are shown in the table below:
Light
Status
Describe
FIX
On Off
Enter 3D Fixed state. Not in 3D Fixed state.
ERR
On Off
Error! The module does not work properly. No error has occurred and is working properly.
RTK
On Off
Enter RTK Fixed state. Not in RTK Fixed state.
PWR
On Off
The power supply is OK. The power supply is abnormal.
When the Base is working properly, the status of lights ：
PWR and FIX are on，the other lights are off.
When the Rover is working properly, there are two conditions in which the status of lights :
PWR and FIX are on，the other lights are off, that means Rover has been in 3D Fixed state.
PWR, FIX and RTK are on, the other lights are off, that means Rover has been in RTK Fixed state.
Positioning data description
The GRTK module outputs NMEA protocol positioning data by default, connects computer with GRTK module’s Tx2 and Rx2 by USB-to-TTL module, then you can use the serial assistant to read or configure the output message.
GRTK Rover and Base are factory configured, non-professionals do not configure equipment at will.PS: Please set the line break to CR&LF.
Rover with a single antenna
Output messages at 5Hz by factory default:
$GPGGA: Global positioning system fix data
$GPRMC: Recommended minimum data
$GPHDT: Output current heading information
$KSXT: Time, positioning and heading of GNSS receiver
Other message
If needed, you can send ASCII syntax by serial port to configurate it：
$GPGGA: Global positioning system fix data
$GPRMC: Recommended minimum data
$GPHDT: Output current heading information
$KSXT: Time, positioning and heading of GNSS receiver
Other message
If needed, you can send ASCII syntax by serial port to configurate it：
The current version of the GRTK cm positioning system supports the output of NMEA protocol positioning data, the following guidance is based on the Ardupilot firmware(v4.2.0 or higher) using the Mission Planer ground station.
Connection for modules
Have the hardware, including Pixhawk controller, GRTK, radio, battery, etc, shown in Figure 3.1 ready for connection before wiring:
Figure 3.1 Hardware physical diagram
Rover Base and data transmissions need to be supplied separately.
The communication mode between Rover and Base
GRTK can achieve RTK positioning by communicating through independent links between the base station and the rover station or by forwarding the base station data by the ground station.
Independent link
Please connect the COM2 port of the GRTK Rover to the GPS port of Pixhawk and the com1 port to connect the data transmission device that communicates with the Base sideb) Please connect the GRTK Base com1 port to the computer through the serial port
Connect antenna to the GRTK Base and connect the com1 port of the base side to the data transmission device that communicates with the Rover terminal.
Forwarding the base station data by the ground station
Please connect the COM2 port of the GRTK Rover to the GPS port of Pixhawk.
Connect the GRTK Base com1 port to the computer through the serial port.
Open Mission Planner, find the Optional Hardware at the Initial Setup, and select RTK/GPS Inject.
4. Choose the correct com port and click Connect.
5. Wait for about one minute for Base to complete the base station positioning, at this time the red in the RTCM column turns green, and the latitude and longitude information of the current base station is displayed, that is, the ground station has been realized to forward the Base positioning data
Mission Planner settings
GRTK Base supports plug-and-play and does not require additional setup at the ground station. However, before actually using RTK, you need to set the parameters for flight control in MP, and the necessary parameter settings are given below, which can be referred to as follows:
GRTK Base has two modes of operation，self-optimizing base station and fixed base station.
Self-optimizing base station：When it is not clear exactly where the base station will be located, Base will position itself and average itself for a certain period of time after installation as the coordinates of the base station.
Fixed base station: When know the exact coordinates of the base station location will be set up, you need to enter that exact coordinate into the base station.
Self-optimizing base station
Base station default operating mode is self-optimizing base station. Using USB to TTL module to connect the base station serial 2 (Rx2&Tx2) to the computer, the computer runs serial debugging assistant, open the corresponding serial port with the baud rate of 115200. The base station returns the current location information.
Send the following command (PS: Commands need to end with a line break) to base station by serial to complete configuration.
mode base time 60 1.5 2.5
Within 60-second automatic positioning of the base station, or when the standard deviation of horizontal positioning is no more than 1.5 m and that of vertical positioning is no more than 2.5 m, set the average value of horizontal and vertical positioning results as the base station coordinates. Restarting the base station triggers a new calculation and reposition of the datum coordinates. Users can modify parameters according to their needs.
After configuration, send the following command (PS: Commands need to end with a line break) to base station by serial to save configuration.
saveconfig
Fixed base station
Fixed base station mode configuration is divided into two steps, the first step is to obtain the current exact coordinates, the second step is to enter the base station’s precise coordinates into the base station.
Step1: Get the current exact coordinates
Using the USB-to-TTL module to connect the base station serial 2 to the computer, the computer runs the serial debugging assistant, open the corresponding serial port, Baud rate of 115200. The base station returns the current location information.
Send the following command (PS: Commands need to end with a line break) to base station by serial to complete configuration.
mode base time 60 1.5 2.5
Within 60-second automatic positioning of the base station, or when the standard deviation of horizontal positioning is no more than 1.5 m and that of vertical positioning is no more than 2.5 m, set the average value of horizontal and vertical positioning results as the base station coordinates. Restarting the base station triggers a new calculation and reposition of the datum coordinates. Users can modify parameters according to their needs.
Note that the obtained WGS84 coordinates indicate that the base station initialization is complete when the data is stable.
Step2: Enter the exact coordinates of the base station into the base station
Copy the location information of the base station output
Analyze and get longitude, latitude and elevation data
32.02245993006,118.85899391094,68.5505（Please replace it based on the actual measurement data）
The configuration command is generated based on the exact coordinates of the base station
mode base 32.02245993006 118.85899391094 68.5505
Send the configuration command (note that the command needs to end with a line break) to the base station through a serial port.
When the configuration is complete, the following command (note that they need to end with a line break) is sent to the base station through a serial port to save the configuration.
saveconfig
Precautions
With our GRTK Kit, the base station side supports plug-and-play. If only Rover is purchased, the use of other companies’ base station end requires additional RTK base station configuration at the ground station, which does not guarantee compatibility and positioning accuracy.
This product is positioning equipment, which needs to search for satellite positioning, try to test it in the open and undisturbed site.
The positioning status of GRTK should be mainly decided by the ground station.
BLIKVM is a Open KVM, it has three versions: CM4 Board, Raspberry HAT, PCIE Board. This device helps to manage servers or workstations remotely, regardless of the health of the operating system or whether one is installed. You can fix any problem, configure the BIOS, and even reinstall the OS using the virtual CD-ROM or Flash Drive. Here you will find comprehensive information about all aspects of the operation of BLIKVM. Join our BLIKVM Discord Community for Support, FAQ & News!
Features
Video capture (1080P 60Hz)
Keyboard forwarding
Mouse forwarding
ATX
Fan Control
Fullscreen mode
Paste text from clipboard
VPN support
Mass Storage Drive (emulate a CD-ROM or Flash Drive)
Multiport KVM over IP
OLED to display system info, like temp, uptime, IP
3、Connect BLIKVM to the computer according to the diagram below:
HDMI IN and otg port must be connected to the computer. ATX too, but it’s optional,read below. There should be no USB hub between BLIKVM and the computer, as some UEFI/BIOS cannot detect them at the boot stage. BLIKVM supports 1080p60Hz or lower about HDMI source.
Connect Ethernet to the network and PWR IN to the BLIKVM power supply.
To manage the power of your computer, you will connect CN-ATX port to the computer.The user can use the ATX cable provided with the product to connect the product and the motherboard ATX switch of the controlled computer. The length of the ATX cable is 60CM, you can also use the double female Dupont cables.
1、If you use raspberry pi computing modules such as CM3 or CM4 EMMC，you can initialize EMMC through the usbboot. If you use an SD card, you can see the 2 part directly. First, use the jumper cap to short the boot pin.Then connect the data cable to the USB OTG interface.Power on blikvm and observe the act light, the green light is always on.Taking Ubuntu system as an example:
# sudo apt-get install libusb-1.0-0-dev
# git clone --depth=1 https://github.com/raspberrypi/usbboot
# cd usbboot
# make
# sudo ./rpiboot
If the content shown in the figure below appears, it indicates that EMMC initialization is successful.
2、Run RPi Imager:
3、Press CHOOSE OS and select Use custom image at bottom of the list:
4、After clicking on this item, select the image file (.img.xz), then click CHOOSE STORAGE.
5、Insert the memory card into the card reader. Choose the card reader from this list. Be careful and choose the right device:
6、After choosing the memory card, press the WRITE button. Confirm the operation when you are asked about it:
7、Wait for the process to finish. Get yourself a coffee or do some stretching:
8、Remove the memory card after successful completion:
The product comes standard with a monochrome OLED display with a resolution of 128×64, and the chip is SSD1306. The user connects the display to the product with the wiring of the display.
The module is connected to CM4 through the I^2^C interface. The wiring definition is shown in the following table. This is a library for the monochrome OLEDs based on SSD1306 drivers.
Follow the method below to enable OLED(Use the latest v3-hdmi-rpi4-latest.img,IIC is enabled by default).
$GPGGA: Global positioning system fix data
$GPRMC: Recommended minimum data
$GPHDT: Output current heading information
$KSXT: Time, positioning and heading of GNSS receiver
$GPGGA: Global positioning system fix data
$GPRMC: Recommended minimum data
$GPHDT: Output current heading information
$KSXT: Time, positioning and heading of GNSS receiver
