Atlas Copco PowerMACS 4000, Руководство пользователя

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Peripheral Devices
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8.14.4.10 GetPLCStringEx
Description: This method reads 40 consecutive bytes from the PLC output data area for ExtCom_API.
The read data is returned as an ASCII string.
Note! Variables declared as STRING in the PLC are prefixed by two Short integers (four
bytes) where the first short specifies max possible length of the string calculated as Max
length
– 80. The second short defines the strings current length. That is, the first character
of the string is located at offset 4 (fourth byte). All PLC strings are also terminated with a
NULL (0) character. This method
does not handle the four leading bytes.
Example : To read the string declared as below from PowerMACS station 1
MyString AT %QB 2600 : STRING40;
you should call:
MyApi.GetPLCStringEx(1, 2604, Value)
Return type: A RetCodeEnum value.
Syntax: object. GetPLCStringEx (Station, Address, Value)
Obj./Arg. Type Dir Description
object Api The Api object to operate on.
Station Integer In Specifies which stations PLC to access. Range 0
– 15 where
0 correspond to the station connected to the API device.
Address Integer In Specifies the offset in the PLC area of the first byte to read.
Range 0
– 999.
Value String Out The read data interpreted as a string.
8.14.4.11 SetPLCStringEx
Description: This method writes the specified string to the PLC input data area for ExtCom_API as 40
consecutive bytes. Each byte will be set to the ASCII value of the respective character. See
also the note for SetPLCString.
Return type: A RetCodeEnum value.
Syntax: object. SetPLCStringEx (Station, Address, Value)
Obj./Arg. Type Dir Description
object
Api
The Api object to operate on.
Station Integer In Specifies which stations PLC to access. Range 0
– 15 where
0 correspond to the station connected to the API device.
Address Integer In Specifies the offset in the PLC area of the first byte to write to.
Range 0
– 999.
Value
String In The data to write.