Logix5000 Controllers General Instructions - SLAC Confluence

ASCII Serial Port Instructions (ABL, ACB, ACL, AHL, ARD, ARL, AWA, AWT) 575Each string data type contains the following members:Name Data Type Description NotesLEN DINT number of charactersin the stringThe LEN automatically updates to the new count of characters whenever you:• use the String Browser dialog box to enter characters• use instructions that read, convert, or manipulate a stringDATA SINT array ASCII characters ofthe stringThe LEN shows the length of the current string. The DATA member may containadditional, old characters, which are not included in the LEN count.• To access the characters of the string, address the name of the tag.For example, to access the characters of the string_1 tag, enter string_1.• Each element of the DATA array contains one character.• You can create new string data types that store less or more characters.ASCII Test For Buffer Line(ABL)The ABL instruction counts the characters in the buffer up to andincluding the first termination character.Operands:Relay LadderABLASCII Test For Buffer LineChannel ?SerialPort Control ?Character Count ?ENDNEROperand Type Format DescriptionChannel DINT immediate 0tagSerial Port SERIAL_PORT_ tag tag that controls the operationControlCharacterCountCONTROLDINT immediate 0During execution, displays the number ofcharacters in the buffer, including thefirst set of termination characters.Structured TextABL(ChannelSerialPortControl);The operands are the same as those for the relay ladderABL instruction. You access the Character Count value via the .POSmember of the SERIAL_PORT_CONTROL structure.Publication 1756-RM003I-EN-P - January 2007