Year ago I started to design my own project. I named my project KhatkaPi.
I have designed and already tested baseboard to support Raspberry pi 5 running Openplotter open source project software and provide exceptional protection for the electronics in marine environment. More information about the project below the picture.
Project is based on several opensource projects ideas and I am obligated to share it to community.
If somebody interested, I will publish all you need to build it yourself or order it to build offshore.
It comes pretty expensive to build just couple boards to get to realistic price order must to be at least 10-20 boards.
If we find 10 or more people who want them I think I can host order and make them available for wide testing. I am pretty sure cost will be about $85-90 per board.
For 20 boards batch we may get to $65-70.
![[Image: 5908.png]](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjwkt1rcUeC1EALki4F36mmrsIqcPwe4NxArDa6MtXBEOqUTpg-EmIdYShXl22TQzu8aYp-WlFKsxHLP-QW_n0IKWG02SmqbIwCqjq5EFullP7KpLfqnkMMfhnt-bUZfKxz4kO4Yzy8f2OM_5rMyXrKO7-k7yS1CiGLykyxLY4zwT6wXbF7JVkaG1ZyMrxy/s1053/5908.png)
Schematic and PCB document
I have designed and already tested baseboard to support Raspberry pi 5 running Openplotter open source project software and provide exceptional protection for the electronics in marine environment. More information about the project below the picture.
Project is based on several opensource projects ideas and I am obligated to share it to community.
If somebody interested, I will publish all you need to build it yourself or order it to build offshore.
It comes pretty expensive to build just couple boards to get to realistic price order must to be at least 10-20 boards.
If we find 10 or more people who want them I think I can host order and make them available for wide testing. I am pretty sure cost will be about $85-90 per board.
For 20 boards batch we may get to $65-70.
Schematic and PCB document
General design strategy points
- Designed for Rpi5 .
- No special drivers required.
- No proprietaty software required.
- Intentionally designed as Baseboard form factor rather HAT.
- You may use any heatsinking cases and NVRAM SSD adapters.
- Rpi and peripherals naturally installed in IP67 box to protect from elements.
- Provides some additional separation between external interfaces and Rpi.
- You may use any heatsinking cases and NVRAM SSD adapters.
- Fits in standard IP 65-67 Electrical Project box 11.42" x 8.27" x 3.94"(290 x 210 x 100 mm).
- All interfaces protected from ESD up to 15KV air discharge and 8KV contact discharge
- Board designed to minimize loss in case of lightning strike, user mistake or other equipment malfunction.
- In most cases uses COMMON GROUND rather galvanic isolation approach to protect against lightning strike.
- However, most interfaces have isolated data lines to protect Raspberry Pi from damage.
- External interfaces have separated power regulators for redundancy and extra protection.
- Sure board is double coated with high grade conformal coating to protect electronics from moisture and salty air.
Features:
- Input power over voltage protection up to 40V.
- Input power under voltage protection <9V to save battery from deep discharge.
- Connector for the switch to override add under voltage protection (down to 6V) in case of emergency.
- Independent 5V power regulator for Raspberry. 6A maximum power capacity to support future Rpi and cover any inrush power surges.
- Connectors to connect external switches and on board buttons for System power control.
- Power On (hard power ON).
- Power Off (hard power OFF).
- Shutdown button.
- Power On (hard power ON).
- Auto power off all but AIS when Rpi completed shutdown.
- Switched 12V output (up to 4A) providing power to auxiliary devices when Raspberry is power on.
- Place to install HDMI splitter next to raspberry.
- Capability to use two mirrored displays from one Rpi w/o software tricks
- Additional protection for Rpi HDMI interface.
- Splitter can be powered USB A connector.
- As an option splitter can be powered from HDMI interface, but it will require sope changes inside the splitter.
- Capability to use two mirrored displays from one Rpi w/o software tricks
- On the board interfaces:
- On board ICM-20948 based IMU
- sensor located on the far corner of the board to have minimal interference with on board magnetic fields.
- sensor located on the far corner of the board to have minimal interference with on board magnetic fields.
- PWM controlled FAN
- installed on the board to run air inside the box to provide better heat distribution and let raspberry transfer heat to external box surface.
- installed on the board to run air inside the box to provide better heat distribution and let raspberry transfer heat to external box surface.
- Socket for Arduino Nano to be used as weather sensors controller based on open source project Pypilot - weathersensors.
- On board barometric pressure sensor BMP280 connected to weathersensors board.
- Isolated serial connection to Raspberry
- Powered form switched 12 volt
- external connector lines ESD and overvoltage protected.
- On board barometric pressure sensor BMP280 connected to weathersensors board.
- 3 Connectors for 1-Wire onterface sensors
- Interface for External temperature sensors.
- Connectors lines ESD and overvoltage protected.
- Interface for External temperature sensors.
- On board ICM-20948 based IMU
- External interfaces:
- I2C interface connector
- if you wish to use external IMU or other I2C devices.
- Interface ESD protected, but not isolates.
- Only distance or in the box connections recommended.
- if you wish to use external IMU or other I2C devices.
- Two NMEA 0183
- Two full isolated and protected NMEA 0183 interfaces.
- Intended to use one for Depth sounder
- Two full isolated and protected NMEA 0183 interfaces.
- Interface to connect Maiana AIS/GPS
- Maiana direct connection with RJ45 connector
- Power and transmit control external switches connectors.
- Independent 3.3V regulator for interface.
- On the board indicators.
- isolated serial interface.
- Maiana direct connection with RJ45 connector
- Interface for the PyPilot Motor controller.
- Serial data lines are isolated and protected.
- 5V power is provided from separated from Rpi regulator.
- Serial data lines are isolated and protected.
- Auxiliary micro-controller serial interface.
- Microcontroller provides access to Rpi GPIO signals over serial interface.
- For example remote hard buttons module will be designed.
- Auxiliary micro-controller serial interface isolated and protected.
- Microcontroller provides access to Rpi GPIO signals over serial interface.
- Two four-port USB hub (total 8 ports)
- All 8 ports have 12kV direct discharge ESD protection and common mode filters.
- Each hub has independent power regulator with 2A load capacity for each group.
- All 8 ports have 12kV direct discharge ESD protection and common mode filters.
- Two 5V power output
- two additional USB ports with power only outputs. Up to 1.5A may be used total
- two additional USB ports with power only outputs. Up to 1.5A may be used total
![[Image: 59089.png]](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDISQp8fKd3wdyEauK5By6n9kwOg3wM9lpZgHxupcTVw_d5sU8bJBr5DTX0cuYpmaS5clgsjyNUUNf9lG_fRs8NCcQ7ccVKTR0lJLfagkZ8GR1HEilVxqmn0bYAynU_aDoSwdK6VTRy8q5D1dLjR2Ap9rf94b0tec7e8IfWdvWwuZRjOKDqzG5fOXg1LLx/s1581/59089.png)
- I2C interface connector
![[Image: IMG_0412.HEIC]](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhmwjd4N_NSB8ynetBQztO9gDajxuPhDDAfB-emB-6vq0t_Juy2AB8Wt5D9-QwH6hU_DTjlsoL1YglKvSAJK7PrYrskn-YMqGFLTbKXkhanT_9imnbJXuYO3rh6al7ddGVK8xwNjjpumvcN1LuQeRWAFix_lAWqjw9SW5eyuJZBurIR2Ao4E5sdUmoqeykK/s1865/IMG_0412.HEIC)