Reading data from my Scuba Diving computer after Linux removed IrDA support

Posted by ads on Saturday, 2019-07-13
Posted in [Hardware][Linux][Scuba-Diving]

When I go Scuba Diving, I use two diving computers. It’s always good to have a fallback, right? My main computer is a ScubaPro Uwatec Galileo Luna. That’s a wrist mounted computer with hoseless air-integration. That means that a sender is connected to the first stage of the regulator, and it transmits data to the wrist computer. In addition the computer records data like depths, consumption, temperature, alarms ect. My fallback is an air-integrated console mounted Suuntu Cobra. I check this computer too when I’m under water, but mostly for the most conservative reading for the safety stop.

The Luna computer has an IrDA port, and using a USB Infrared Adapter (I’m using an IRwave 3902B500) I was able to read all the dive logs from the computer into Subsurface. However at some point, Linux decided that IrDA is no longer worth supporting, and they removed the support and modules in Linux 4.17.

Bummer.

It’s possible to read the most basic data about each dive on the computer display itself, but you won’t get all the details, and the profiles.

After pondering the problem for a while, I decided to setup an old laptop, and use this system for the dive computer. Looking back, I found that Ubuntu 18.04 LTS is already “too young”, and the kernel too new. IrDA support is no longer available. Therefore I had to go back to 16.04 LTS, download the DVD installer image, find a DVD writer somewhere, and burn the image on a blank disk - which I also had to buy first. Anyway, after a while I had a working Linux system on the old laptop, installed Subsurface and irda-utils.

When I plug-in the USB IrDA Adapter, I see the following in lsusb:

ID 9710:7780 MosChip Semiconductor MCS7780 4Mbps Fast IrDA Adapter

From there, I need a root shell, and have to enter the following commands:

1
2
3
4
5
6
modprobe mcs7780
modprobe ircomm-tty
iwconfig irda0
ifconfig irda0 up
irattach irda0 -s
irdadump

Once you place the activated dive computer in front of the USB adapter, you should see that both deviced exchange information. Stop the dump with Ctrl+C.

In Subsurface, you can now use device /dev/ircomm0 to communicate with the dive computer.


Categories: [Hardware] [Linux] [Scuba-Diving]

Share: