Have you recently purchased a boat? Transferring a radio and license to a new craft? Need to reset the MMSI in your AIS?
The bad news– many restrictions are in place on AIS units which prevent the MMSI numbers from being updated. Valid reasons for this include prevention or misuse of identification for intentionally nefarious or illegal purposes. But this preventative measure creates a dependency for most of the sailing and recreational craft community to find and locate dealers or installers, often in remote places or other countries, adding costs and difficulties to the lifestyle.
Additionally, current software options are either locked (preventing you from deleting the prior MMSI), or don’t connect to most older AIS units, which prevent the options in many of the guides / forums on line from working (like this one).
The good news– you can delete the old MMSI from any AIS using this guide without sending the unit to a different country or hire a professional installer. We used a Linux-based laptop, a serial cable, and the code below on a 2004-era Comar CSB200 to erase and reset our MMSI. The trick is using open-source, readily available software and the right code to reset / erase the former MMSI number.
Please note: the information has been compiled as a complete reference built from personal experience and several supporting blogs, hopefully it works for you. Reach out if you need a hand.
What is an MMSI?
An MMSI # is a ‘Maritime Mobile Service Identity‘ number, a unique 9-digit code that identifies a craft’s DSC radio and AIS transponders (‘automatic identification system’). The MMSI numbers provide quick identification through either networks for friends and family, rapid response teams, neighboring vessels, and anyone else wishing to monitor marine and air traffic.
Why is resetting your MMSI or setting your MMSI # to your correct number important? The primary reason is for proper identification of your craft, especially if there are any emergencies or reasons necessary for finding and aiding your craft. The second reason is to ensure proper compliance with countries such as Greece, where new regulations enforce that owners of radios have the proper licenses to broadcast their VLF radios and that the MMSI numbers match those of the craft on the AIS network. Also, as a boat owner who carried a prior owners’ incorrect MMSI for a while, it was annoying to be confused with the former owners, especially when our boat was re-flagged in a different nation after the transfer of ownership and friends/family couldn’t reliably search for and find our vessel…. or wondered why the vessel didn’t match the descriptions on the networks.
Here are the basic steps to reset your MMSI, covered in this post:
- Download Software
- Plug the AIS into your computer
- Erase (Delete) the prior MMSI number
- Enter a new MMSI number
- Sail!
Download the software
You’ll need a laptop. ANY operating system will do to reset or delete your old MMSI.
Our preference is Serial Port Assistant (Windows, Linux, AND Mac!) Try downloading using any ‘add software’ assistance you already have on your OS before using the link included here; it’ll be easier than building from the github repository.
Why not use ProAIS or ProAIS2? You can. Try it. But a warning: ProAIS will likely struggle to either connect with your AIS, especially if the AIS is old, and we found that ProAIS2 doesn’t accept your MMSI delete commands on the Serial Data tab. But try it anyway, maybe you’ll get further than we did.
Connect the AIS to your laptop
If you’re reading this guide, you likely have a serial connection on the AIS (9 pin, see this unaffiliated link here to the Amazon overlords).
On Windows?
Wait! Install any drivers that came with the serial cable if you can find them, then connect the cable. You might also require a USB to USB-C adapter to fit the little USB ports.
Open the software, run the commands in the next section.
On Linux or Mac? No problem. Just connect the cable
You’ll need WRITE access to the port. Using the terminal (command line!)- Ctrl-T or Special key-T or find it and click on it….
## Add a group called 'dialout'
sudo groupadd dialout
## Add yourself to the group
sudo adduser scott dialout
## Run the serial port assistant program as root anyway, just because hey, make sure you've the power
## on Linux
sudo -i
flatpak run io.github.KangLin.SerialPortAssistant
## on Mac-- special key click (or right click?) on the Serial Port Assistant icon, run as administratorLink your AIS and Software
Ok, now you need to tell your software how to talk to the AIS.
In ProAIS or ProAIS2, this is easy- maybe, it might actually not work at all. Select the appropriate ‘comm’ from the dropdown menu, which is probably comm 5, and hopefully it’ll connect for you.
In Serial Port Assistant, use the following parameters to connect to your serial port AIS:
- Serial Port: ttyUSB0 (or similar)
- Baud Rate: 38400
- DataBit: 8
- Parity: None
- StopBit: 1
- Flow Control: None
- Receive Settings: UTF8
- Send Settings: UTF8
…. then click the green ‘Play’ button.
Erase your old MMSI from the AIS
There are two different blocks of code to do this. We only have experience with the former, but have included the latter as it has ‘apparently worked for some people’.
Delete MMSI Code Option #1
Enter all three of the following lines, with line breaks, into the ‘transmission box’ in the lower right corner of Serial Port Assistant OR in the ‘send code’ box at the bottom of the Serial Data on ProAIS/ProAIS2. You can copy and paste this code directly.
$PSMT,0,3,0x2C75B2FA,1,nvdeli "mmsi",52*45
$PSMT,0,3,0x2C75B2FA,1,delay 100,53*06
$PSMT,0,3,0x2C75B2FA,1,bootcmd 0,56*0B… Send!
The first line deletes the old MMSI number, the second line delays enough time to let the delete command happen, and the third line reboots the AIS. Done!
Delete MMSI Code Option #2
Enter both of the following lines, with line breaks into the ‘transmission box’ in the lower right corner of Serial Port Assistant OR in the ‘send code’ box of the Serial Data on ProAIS/ProAIS2. You can copy and paste this code directly.
$PSRT,012,,,(--QuaRk--)*4B
$PSRT,RDP*6F… Send!
The first line is an authorization code, and the second is the reset data profile for the unit. Note: in other blogs, this series works fine for some people, not for others. Our Comar CSB200 from 2004 did not accept this code.
Enter New MMSI Number
For this, currently, we don’t yet know the code to do this outside of using ProAIS(2). If we find it, we’ll edit this post to update it, but our current recommendation to set a new MMST is to now use or find someone with an Windows OS laptop and any (working) ProAIS software… likely only ProAIS2.
If you used the first code block above…. simply start ProAIS2, connect to the AIS unit as indicated above, and you can enter your new MMSI. Click ‘accept’ when presented with a warning about falsifying your AIS, if you wanted to do so. Not for us. Take the time to review the other information including boat name, call sign, and location in meters of your GPS relative to your boat dimensions.
If you used the second code block above, start ProAIS2, and re-enter all of the details, including your boat name, call sign, MMSI, and location in meters of your GPS relative to your boat dimensions.
Good luck, we wish you happy sailing. Be sure to check out the other posts on this blog!
