User`s manual

Data Management and I/O Words
104
Diagnostics
Error monitoring The internal voltage supply (Vcc) is supplied by the I/O unit. Vcc is monitored and a
reset signal is generated if Vcc is outside the tolerance.
The potentially isolated voltage (Vcx) for the INTERBUS interface is generated using
a DC/DC converter and is not monitored.
A SUPI protocol chip controls the display LEDs that provide data transfer information
(bus active, remote bus check, remote bus disabled, , see section Display and
Operating Elements of the relevant module description) and the operating elements
(with components for the use of fiber optic technology).
The supervision time of the internal watchdog is 640ms and is signaled via the "BA"
LED.
An I/O error created by the I/O Unit generates a module error in the INTERBUS
adapter. This is recognized by the master and can be evaluated by the application
program. A module error does not automatically lead to a bus failure.