Length
Use this element when an element indicating the data length is included in a packet.
• When sending: Calculates the data length of a specified range, and adds the result to a send packet.
• When receiving: Verifies the data (value) corresponding to the length in the received data as the data length of the specified
range.
For data examples of length, refer to Page 217 Data examples of Length.
Window
Item
Description
Element Name
Set the name of the element.
Code Type
Select a format of the data length.
• ASCII Hexadecimal
• ASCII Decimal
• HEX
Data Length
Select the data length on the line.
The range is 1 to 4.
Data Flow
Forward Direction
(Upper ByteLower Byte)
Reverse Direction
(Lower ByteUpper Byte)
Byte Swap
(by Word)
Calculating
Start
Select the start packet element numbers for the calculating range.
Range
The range is 1 to 32.
End
Select the last packet element numbers for the calculating range.
The range is 1 to 32.
Considerations for configuring packet element
• Only one terminator can be used in a packet.
• To configure the length, one or more other elements are needed.
When
Sends a calculated length from the upper byte.
sending
When
Receives data from the upper byte.
receiving
When
Sends a calculated length from the lower byte.
sending
When
Receives data from the lower byte.
receiving
When
Sends a calculated length swapping the upper byte and
sending
lower byte by word.
When
Receives data swapping the upper byte and lower byte
receiving
by word.
6 PREDEFINED PROTOCOL SUPPORT FUNCTION
6
Remarks
Data flow setting is
invalid when data length
is 1 byte.
Data flow setting is
invalid when data length
is 1 to 3 byte.
Refer to Page 219.
179
6.7 Packet Setting