Diagnostic; Short Circuit; Line Break; Interrupt - Addi-Data APCI-3701 Technical Description

APCI-3701
9.7

Diagnostic

The board disposes of a diagnostic function which under certain circumstances
can detect a short circuit or an open line on the primary circuit as well as on the
secondary circuit.
The short-circuit detection on the primary circuit is activated continuously. The
other diagnostic functions are activated by software functions.

9.7.1 Short circuit

On the primary circuit the supply voltage of the power buffer is controlled. If a
short circuit occurs, a voltage drop is detected. This information is returned by
software. (See the software diagnostic function).
In case of short circuit the power buffer disposes of internal fuses which switch
the outputs off.
On the secondary circuit the number of the channel which caused a short circuit is
returned by software.

9.7.2 Line break

In case of a line break on the primary circuit a software function controls if at
least one of the n connected transducers is not correctly connected. The user is to
make sure that all transducers are correctly connected.
On the secondary circuit the number of the channel which has a line break is
returned by software.
9.8

Interrupt

Below are the possible interrupt sources:
short circuit on the primary circuit
-
timer has run down
-
end of conversion (EOC)
-
end of sequence (EOS)
-
the sequence counter has run down
-
DMA end of transfer
-
FIFO memory is full
-
9.9

Timer

A 12-bit timer is available onboard to generate an interrupt. It can be pre-
programmed with 3 different clock units.
Table 9-1: Timer time intervals
Time unit Range of the delay time in the time unit
µs from 0 to 4095 µs = 4.095 ms
ms from 0 to 4095 ms = 4.095 s
s from 0 to 4095 s = 1 h 08 mn 15 s
Functions of the board
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