MOST Tiny 3G

Original vehicle control unit for setting up a MOST data bus system. In conjunction with a gateway and the MOST PC USB Interface 7402013, a complete MOST ring can be set up (without multimedia functionality!). The device has an optical display of the ring break diagnostic line and a 7-segment display to show the node address and the logical MOST address. The two optical fibers are connected to the other ring in a Plexiglas coupler. This allows the communication setup to be observed and errors to be built in.

General features:

Control unit for MOST system clock generation
optical interface for fiber optics
Error simulation on fiber optics
Display of the node address
Display of the logical ring address
Ring break diagnostic cable according to ECL standard
Optical display of the ring break diagnosis status
Error simulation on the ring break diagnostic line
Self-Diagnostic Capable

Self-diagnosis and troubleshooting:

The device is connected to a gateway control device, e.g. via the diagnostic interface CAN+USB 7379803 capable of self-diagnosis with the options:

Read fault memory
Show actual values
Perform actuator test
Parameter setting of the control unit
Ring break diagnosis

 Faults:

• Various errors can be applied to the optical fibers. Among others, there is the possibility of installing an error that can only be found using the "-3 dB" setting of the ring break diagnosis!
• Determination of the maximum bending radius of fiber optics
• The ring break diagnosis line itself can be subjected to errors directly on the device, which can lead to limitations or failure of this line.

 Data bus analysis:

In connection with the MOST PC USB Interface 7402013, the optical signals can be recorded with the oscilloscope 739007. The control data can be recorded and evaluated on the PC via the integrated USB interface.

Learning content:

Physical-optical fundamentals of light
Construction of fiber optics
MOST topology
MOST data protocol
Logical and physical node addresses
Ring break diagnosis
Optical errors and their effects
Optical measurements on fiber optic cables
Electrical measurements on fiber optic cables
Digital transmission of audio signals
Optical coupling losses
Optical attenuation

 The front panel of the device is printed in color so that the MOST data bus can be easily identified visually. To simplify the experimental set-up, the voltage supply terminals 30 and 15, the ring break diagnosis line and the ground are connected through from left to right on 4 mm safety sockets.