Zach Dockter 9 years ago in Expansion modules / XT2 updated by Gustav Widén (System support) 9 years ago 1
Is the XT2 being phased out? If so, is it going to be replaced with another expansion module that can handle 2 seperate CAN lines?
Hi Zach,

The XT2 is not in phase-out yet, but it is getting old so it is a very relevant question.

The way I see it, the XT2 has got three unique features:

-E-gas servo output (H-bridge).
The E-gas servo output is still being used in some applications with smaller engines where there is no J1939 interface.
You can build this using a pair of PWM outputs on e.g. an MC2, but it is easier to use an XT2.
-High frequency based COUT with sinusoidal ripple
The XT2 COUT has traditionally been used on hydtrostatic transmissions where there needs to be a very smooth ripple. But nowdays most of the applications I see just use a regular COUT:s on MC2 or XA2 with an increased PWM frequency for driving the hydrostatic pumps.
-J1939 gateway
In the days of the MDM and the IQANdevelop system, the XT2 had to be used as J1939 gateway.
Now on the IQANdesign platform where all master modules have two to four CAN buses, this gateway function on the XT2 is very rarely being used.
Also, you can mix J1939 traffic and IQAN expansion bus traffic on the same physical bus, so even if you are running low on CAN buses on your master, you don't need to use the XT2.
Compared to mixing IQAN expansion modules and J1939, and using an XT2, the bus utilization on the IQAN expansion bus would be almost the same, since all J1939 data that passes through the XT2 must run on that bus also.
A drawback of using the XT2 as J1939 gateway is that there are fixed limits on number of PGN:s it can handle, and it does not support all features, e.g. DM2 viewing.

In general, I would not recommend designing a new system with the XT2 as J1939 gateway, it is almost always better to connect the J1939 bus on the master module(s)