Omron SRM1 - PROGRAMING 02-2001, Руководство по программированию

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3-1 Section Analog I/O Units
174
Writing Analog Output Set Values
A ladder program can be used to write data to the output word where the set val-
ue is stored. The output word will be “n+1” when “n” is the last output word allo-
cated to the CPU Unit, or previous Expansion Unit or Expansion I/O Unit.
(n + 1)
Sign bit
(Used when the output sig-
nal range is –10 to 10 V.)
Set value (Hex: 00 to FF)
0 0 0 0 0 0 0
1, 2, 3... 1. The set value range is 0000 to 00FF when the output signal range is 0 to
10 V/4 to 20 mA.
2. The set value range is divided into two parts: 8000 to 80FF (–10 to 0 V) and
0000 to 00FF (0 to 10 V) when the output signal range is –10 to 10 V.
3. If FF is input, 0 V/4 mA will be output.
4. If an output value is specified, the following bits will be ignored.
•
Output range of –10 to 10 V: Bits 08 to 14
•
Output range of 0 to 10 V/4 to 20 mA: Bits 08 to 15
Startup Operation
After power is turned ON, it will require two cycle times plus approx. 100 ms be-
fore the first data is converted. The following instructions can be placed at the
beginning of the program to delay reading converted data from analog inputs
until conversion is actually possible.
Note Analog input data will be 0000 until initial processing has been completed. Ana-
log output data will be 0 V or 0 mA until the range code has been written. After the
range code has been written, the analog output data will be 0 V or 4 mA if the
range is 0 to 10 V, –10 to 10 V, or 4 to 20 mA.
SR 25315
(Always ON Flag)
TIM 000 will start as soon as power turns ON.
After 0.2 to 0.3 s (200 to 300 ms), the Comple-
tion Flag for TIM 000 will turn ON, and the con-
verted data from analog input will be read from
IR 001 and stored in DM 0000.
T005
MOV (21)
001
DM0000
TIM 000
#0003
Handling Unit Errors
If an error occurs in an Analog I/O Unit, the Error Flags in AR 0200 to AR 0204 will
be turned ON. The addresses of the Error Flags are in the order that the Expan-
sion Units and Expansion I/O Units are connected in the PC, with AR 0200 used
for the Expansion Unit or Expansion I/O Unit closest to the CPU Unit. Use these
flags in the program when it is necessary to detect errors.
When an error occurs in the Analog I/O Unit, analog input data will be 0000 and
0 V or 4 mA will be output as the analog output.