HALPI2 Boat Computer

[mairas]

Hi all,

For the past few months, I have been developing HALPI2, a Raspberry Pi Compute Module 5 based marine computer. HALPI2 has a custom-designed carrier board and is loaded with useful features such as integrated CAN bus (NMEA 2000) and RS-485 (NMEA 0183) interfaces, a superb power supply design with a short-term energy storage for controlled shutdowns, on-board M.2 SSD interface, 4x USB3 ports and so on.

HALPI2 is designed for a 200x130x60 mm waterproof diecast aluminium enclosure that also doubles as the CM5 module heatsink. The enclosure comes standard with good connectivity and room for expansion.

Here's a photo of a prototype device:



HALPI2 is open hardware, the PCB designs are available at https://github.com/hatlabs/HALPI2-hardware.

The development is well under way and I hope to have the first customer devices shipped end of May or in June. I've written some posts on the development here: https://hatlabs.fi/posts/
As a final commercial blurb, I have also enabled pre-orders for the device. Pre-orders have a 15% discount compared to the final pricing and will be shipped on a first-come, first-served basis. See here: https://shop.hatlabs.fi/products/halpi2-computer

[Mason]

Hi all,

For the past few months, I have been developing HALPI2, a Raspberry Pi Compute Module 5 based marine computer. HALPI2 has a custom-designed carrier board and is loaded with useful features such as integrated CAN bus (NMEA 2000) and RS-485 (NMEA 0183) interfaces, a superb power supply design with a short-term energy storage for controlled shutdowns, on-board M.2 SSD interface, 4x USB3 ports and so on.

HALPI2 is designed for a 200x130x60 mm waterproof diecast aluminium enclosure that also doubles as the CM5 module heatsink. The enclosure comes standard with good connectivity and room for expansion.

Here's a photo of a prototype device:



HALPI2 is open hardware, the PCB designs are available at https://github.com/hatlabs/HALPI2-hardware.

The development is well under way and I hope to have the first customer devices shipped end of May or in June. I've written some posts on the development here: https://hatlabs.fi/posts/
As a final commercial blurb, I have also enabled pre-orders for the device. Pre-orders have a 15% discount compared to the final pricing and will be shipped on a first-come, first-served basis. See here: https://shop.hatlabs.fi/products/halpi2-computer

Thank you for your work on this!! I was thinking of designing something similar but it's great to see that you've already done it. I see that this fits HATs: does it only fit one HAT or can you stack two at the same time?

Mason

[mairas]

Thank you for your work on this!! I was thinking of designing something similar but it's great to see that you've already done it. I see that this fits HATs: does it only fit one HAT or can you stack two at the same time?

There's room for two HATs. There's also a higher variant of the same enclosure, so in principle it would be possible to have an alternative with more HATs (one extra would be my guess) and possibly more panel connectors, but I'll try to get the basic version out first without even considering such options... :-)

[Mason]

Thank you for your work on this!! I was thinking of designing something similar but it's great to see that you've already done it. I see that this fits HATs: does it only fit one HAT or can you stack two at the same time?

There's room for two HATs. There's also a higher variant of the same enclosure, so in principle it would be possible to have an alternative with more HATs (one extra would be my guess) and possibly more panel connectors, but I'll try to get the basic version out first without even considering such options... :-)

Thanks! Is your GNSS HAT compatible with use with the dAISy HAT?

[mairas]

Thanks! Is your GNSS HAT compatible with use with the dAISy HAT?

It would appear so. The MAX-M8Q HAT communicates using UART on GPIOs 14 and 15 while the dAISy HAT uses UART on pins 8 and 10 (and some non-essential optional pins that seem to conflict with HALPI2's RS-485).

---

I did some power and thermal performance measurements using the latest proto. Even at 100% CPU load, the CPU temperature seems to peak at just 45°C. Pretty cool. (Pun intended.)

https://hatlabs.fi/posts/2025-05-02-halp...rformance/

[Mason]

Thanks! Is your GNSS HAT compatible with use with the dAISy HAT?

It would appear so. The MAX-M8Q HAT communicates using UART on GPIOs 14 and 15 while the dAISy HAT uses UART on pins 8 and 10 (and some non-essential optional pins that seem to conflict with HALPI2's RS-485).

---

I did some power and thermal performance measurements using the latest proto. Even at 100% CPU load, the CPU temperature seems to peak at just 45°C. Pretty cool. (Pun intended.)

https://hatlabs.fi/posts/2025-05-02-halp...rformance/

That's great to hear! Do you know what optional features those pins are used for?

[mairas]

I also wrote about the production preparations and the software: https://hatlabs.fi/posts/2025-05-31_halpi2-update/

[gildas declercq]

Hi,
I am interested, I currently have a rpi4 with MacArthur HAT.
I use the connection to NMEA 2K, NMEA1803, 1W for temp sensor, and will use I2C .

could you confirm the HALPI2 can connect the same ?
thanks

[mairas]

Hi,
I am interested, I currently have a rpi4 with MacArthur HAT.
I use the connection to NMEA 2K, NMEA1803, 1W for temp sensor, and will use I2C .

could you confirm the HALPI2  can connect the same ?
thanks

MacArthur HAT is probably compatible with the HALPI2, although I haven't been able to test it myself.

HALPI2 provides native NMEA 2000 and NMEA 0183, so in that regard, you're all set.

I do not recommend connecting external 1-wire or I2C devices directly to HALPI2 because the GPIO pins are not protected in any way. Instead, I would build a separate interface device using an SH-ESP32 and use Signal K or NMEA 2000 to transmit the data to the HALPI2 computer.

[gildas declercq]

ok thanx, better for me then to stay with rpi and macarthur as it replies to my need to connect natively these devicees
not real intererest to put the macarthur hat on halpi2