B&R BRCOMP1-0 Anwenderhandbuch Seite 174

B&R COMPACT PLC
Inputs/Outputs
OUT0
OUT1
13.8 ANALOG CONVERSION
The analog conversion is only done with a value change. After a power on or a reset (SW or HW)
registers R 1010 - R 1013 and therefore the outputs as well, are set to 0.
1) Value comparison in system interrupt
The value comparison is done in a system interrupt. Only one channel is checked per system interrupt,
i.e., the fastest update time per channel is 20 msec.
2) Direct jump to pointer in operating system
In addition to the value comparison in the system interrupt, a pointer can be jumped to directly from the
program. This pointer references the analog conversion routine (Pointer: $C111). Shorter update times
are accomplished in this way. One channel is checked per call.
Example:
LDD
XGDX
JSR
3) Checking a single channel
This method is used if only one analog output is required. As in point 2 you make a jump to a pointer in
the operating system which references the analog conversion routine (Pointer: $C120). The channel
number is sent to Accu B.
Example:
LDD
XGDX
LDAB
JSR
- 174 -
Description
Contains the values to be converted from channel 0.
Value range:
Signal
±10 V
0 - 20 mA
Contains the values to be converted from channel 1.
Value range:
Signal
±10 V
0 - 20 mA
# $C111 Address of the operating system routine
X 000 Operating system routine call
# $C120 Address of the operating system routine
Channel number (0/1)
X 000 Operating system routine call
Value
-32768 to +32767
0 to 32767
Value
-32768 to +32767
0 to 32767
Address types
R
R