Beckhoff KL2521 Series, Документация

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Access from the user program
KL2521 37 Version: 2.1
Control byte in register mode (REG=1)
MSB
REG=1 W/R A5 A4 A3 A2 A1 A0
REG = 0
bin
: Process data exchange
REG = 1
bin
: Access to register structure
W/R = 0
bin
: Read register
W/R = 1
bin
: Write register
A5..A0 = register address
Addresses A5...A0 can be used to address a total of 64 registers.
Fig. 21: Register mode control byte
The control or status byte occupies the lowest address of a logical channel. The corresponding register
values are located in the following 2 data bytes. (The BK2000 is an exception: here, an unused data byte is
inserted after the control or status byte, and the register value is therefore placed on a word boundary).
Example 1:
Reading of register 8 in the BK2000 with a KL3022 and the end terminal:
If the following bytes are transferred from the controller to the terminal,
Byte Byte 3 Byte 2 Byte 1 Byte 0
Name Data out, low byte Data out, high byte Not used Control byte
Value 0xXX 0xXX 0xXX 0x88
the terminal returns the following type identifier (0x0BBA corresponds to unsigned integer 3022).
Byte Byte 3 Byte 2 Byte 1 Byte 0
Name Data in, low byte Data in, high byte Not used Status byte
Value 0xCE 0x0B 0x00 0x88
Example 2:
Write register 31 in the BK2000 with an intelligent and the end terminal:
If the following bytes ( code word [
}
32] ) are transferred from the controller to the terminal,