Beckhoff KL320 Series, Documentation, Page: 41 / 54

Access from the user program
KL320x 41 Version: 4.4
The main features of the internal data structure are the same for all the intelligent terminals. This data area is
organized as words and comprises 64 registers. The important data and parameters of the terminal can be
read and set through this structure. It is also possible for functions to be called by means of corresponding
parameters. Each logical channel in an intelligent terminal has such a structure (4-channel analog terminals
therefore have 4 sets of registers).
This structure is divided into the following areas:
(A detailed list of all registers can be found in the Appendix.)
Register Use
0 to 7 Process variables
8 to 15 Type register
16 to 30 Manufacturer parameters
31 to 47 User parameters
48 to 63 Extended user area
5.4.1 Process variables
R0 to R7: Registers in the internal RAM of the terminal
The process variables can be used in addition to the actual process image. Their function is specific to the
terminal.
R0 to R5: Terminal-specific registers
The function of these registers depend on the respective terminal type (see terminal-specific register
description).
• R6: Diagnostic register
The diagnostic register can contain additional diagnostic information. Parity errors, for instance, that
occur in serial interface terminals during data transmission are indicated here.
• R7: Command register
High-Byte_Write = function parameter
Low-Byte_Write = function number
High-Byte_Read = function result
Low-Byte_Read = function number
5.4.2 Type register
R8 to R15: Registers in the internal ROM of the terminal
The type and system parameters are hard programmed by the manufacturer, and the user can read them
but cannot change them.
• R8: Terminal type
The terminal type in register R8 is needed to identify the terminal.
• R9: Software version (X.y)
The software version can be read as a string of ASCII characters.
• R10: Data length
R10 contains the number of multiplexed shift registers and their length in bits.
The Bus Coupler sees this structure.
• R11: Signal channels
Related to R10, this contains the number of channels that are logically present. Thus for example a
shift register that is physically present can perfectly well consist of several signal channels.