BECKHOFF KL6071 - Manual (Page 6)

Terminal configuration
4 KL6071
3.2 Register description
The complex terminals can be adjusted to different operating modes or
functionalities. The General Description of Register describes the contents
of the registers, which are identical for all complex terminals.
The terminal-specific registers are explained in the section following to it.
The access to the internal registers of the terminal is described in the
section Register Communication.
3.2.1 General register description
Complex terminals that possess a processor are capable of bidirectionally
ex-changing data with the higher-level control system. Below, these
terminals are referred to as intelligent bus terminals. They include the
analog inputs, the analog outputs, serial interface terminals (RS485,
RS232, TTY etc.), counter terminals, encoder interfaces, SSI interfaces,
PWM terminals and all other parameterizable terminals.
Internally, all intelligent terminals possess a data structure that is identical
in terms of it's essential characteristics. This data area is organized in
words and embraces 64 registers. The essential data and parameters of
the terminal can be read and adjusted by way of the structure. Function
calls with corresponding parameters are also possible. Each logical
channel of an intelligent terminal has such a structure (therefore, 4-channel
analog terminals have 4 register sets.
This structure is broken down into the following areas:
Register Application
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
Process variables
R0 to R7: Registers in the terminal’s internal RAM
The process variables can be used in additional to the actual process
image and their functions are specific to the terminal.
R0 to R5: Terminal specific registers
The function of these registers depends on the respective terminal type
(see terminal-specific register description).
R6: Diagnostic register
The diagnostic register may contain additional diagnostic information. In
the case of serial interface terminals, for example, parity errors that have
occurred during data transfer are indicated.
R7: Command register
High-Byte_Write = function parameter
Low-Byte_Write = function number
High-Byte_Read = function result
Low-Byte_Read = function number
Type registers R8 to R15: Registers in the terminal’s internal ROM
The type and system parameters are programmed permanently by the
manufacturer and can only be read by the user but cannot be modified.