Poseidon M28

Got questions about the Poseidon M28? We have answers!

Do you have questions about the Poseidon M28 Computer? We know there is a lot of information and we are happy to answer any questions you have. Read our FAQ below first and if your question isn’t answered you can complete the form below and we will contact you shortly!

Poseidon M28 FAQ:

Q: Can I use the M28 to update the settings on my SE7EN?

A: Yes you can, using Bluetooth. You no longer need a laptop to change the settings

Q: Can I use the M28 to update the settings on my MKVI?

A: Yes you can, using IrDA. You no longer need a laptop to change the settings

Q: Can I use the M28 to change gases and the PO2 set point underwater on my SE7EN?

A: Yes if it is connected with a cable to your SE7EN.

Q: Can I use the M28 to change gases underwater on my MKVI?

A: No. The M28 cannot connect underwater to the MKVI

Q: Does the M28 replace the paddle on the SE7EN or is it an addition? Can both be connected at the same time?

A: It can replace the paddle, or both can be used at the same time using a splitter cable.

Q: Can I purchase an open circuit only version of the M28?

A: Not yet. The first M28s will all be CCR-enabled. You will be able to use them for open circuit, of course!

Q: Do I need special Software Options, depending on the battery type of my seven?

A: No. The M28 will recognize the battery you use and the battery firmware takes operating and safety priority.

Q: Can the M28 be recharged while connected to the rebreather?

A: No. The M28 needs to be charged via USB

Q: Is the M28 compatible with other rebreathers like the JJ CCR?

A: The M28 can act as a back up computer for most rebreathers, including the JJ, using a Poseidon C-POD or similar digital third cell device.

Q: Is there a user manual for the M28 that I can download?

A: The M28 user manual will be release when the M28 ships so you can’t download it just yet.

Q: What is the difference between the C-POD and the Third Cell Holder?

A: The C-POD is digital; the Third Cell Holder is analogue.

Q: What are the dive planning capabilities of the M28?

A: You will be able to fully plan open and closed circuit dives.

Q: How many open circuit gases are supported?

A: 8 gases are supported.

Q: Is the M28 trimix compatible?

A: Yes

Q: What is the max number of O2 sensors supported and what is the voting algorithm, if any?

A: The M28 will support 3 oxygen sensors and uses Poseidon’s patented sensor validation system.

Q: Can the M28 be used with the Poseidon 3rd Cell Holder?

A: No. You will need a Poseidon CPOD to read a third cell using the M28.

Q: Can the CPOD be used with a normal galvanic cell, or can it only use the Solid State Oxygen Sensor?

A: The CPOD can use either a galvanic cell or a Solid State Oxygen sensor, but only one can fit in the CPOD at any one time. The M28 can read either cell using the CPOD.

Q: Do I have to update my SE7EN firmware to use the M28?

A: Yes. You need to update your SE7EN to firmware v 1.37  to run with the M28. The best way to do this is to update your SE7EN using the RB config tool in the usual way and then connect your M28 to your SE7EN.

Q: If I replace my existing SE7EN computer with the M28, can I update all of the settings from the user interface on the M28?  I would hope the only reason for a Bluetooth connection would be to download dive logs or update firmware.  In other words, I hope it’s as user friendly as my Shearwater Petrel.

A: As well as updating all dive settings on the SE7EN above and below water, the M28 can be used to update firmware and download dive logs on the SE7EN. The M28 can be updated using a WiFi connection to Mac or PC. This is a big advance for all SE7EN divers.


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M28 Configuration Options

The Poseidon M28 “CCR Ready” bundle (0600-200) includes: Poseidon M28 Computer, carrying case, dust bag, charging cable, and bungee cord.

Customers wishing to connect their M28 to their SE7EN will need an additional cable (0000-690).

Customers wishing to connect their M28 to their SE7EN and to a third cell will need:
Splitter Cable (either 6011-061 or 6011-062)
Additional Cable (6011-690)
C-POD (6011-060)
O2 Sensor (6010-206)

Customers who intend to use the M28 with their MKVI as a redundant backup system will need:
Cable (6011-690)
C-POD (6011-060)
O2 Sensor (6010-206)


Poseidon M28: The world’s most powerful computer


Poseidon M28 Package

Poseidon M28

Poseidon M28

Poseidon M28

Poseidon M28

Poseidon M28

Poseidon M28