Innovate Motorsports OT-2 SDK - Manual (Page 63)

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But How Do I Connect?!
If you have reached this point, you now have a wealth of information. You know how to
read MTS packets, configure the OT-1b/2, and even go mucking directly with an ECU.
But you are missing a critical piece of information, getting connected to the OT-1b/2 in
the first place!
This is not an oversight, all of the information that you have learned to this point is
‘transport independent’. That is, it applies regardless of how you connect to the unit. But,
to get anything done, you will need to connect!
Note: The information that follows is not really specific to the OT-1b/2. It can be used
with other devices, like the LM-2, and will be applicable with future devices.
Innovate Transports
MTS is now available over three types of connections, RS-232, USB (IMS USB), and
network (IMS NET). However, on the OT-1b/2, the RS-232 ‘Serial Out’ connector is
limited to ‘in band’ MTS communication only. That is, data packets flow out of it, and it
accepts in-band commands and queries, but it will not accept commands to go into Setup
or Expert modes.
Since this SDK is primarily focused on using those modes, we will limit our discussion to
the other two protocols.
IMS USB
It is beyond the scope of this document to fully cover USB. However a good primer
(from an embedded systems engineer) can be found here:
http://www.computer-solutions.co.uk/info/Embedded_tutorials/usb_tutorial.htm
A reasonable question would be why does IMS USB exist at all? After all, a common
solution to this is to use a USB->Serial chip. Connect to it through your existing serial
interface, and have it appear on the computer as a serial port, which all the serial port
aware software can use as before.
Actually, we tried this, with the original OT-1. Our hope was that this would make device
drivers for all platforms, etc., someone else’s problem (we are big fans of delegating
grief). However, although we used a very popular and reputable USB/Serial chip, it was a
serious support headache.
Precisely because the approach is popular, it is common to have other applications that
are installing the same, or similar drivers, but not always correctly. Another reoccurring
problem is that Windows sometimes sees the MTS in band serial stream as a ‘Microsoft