Beckhoff KL6781, Documentation

Page: 27 / 32

Access from the user program
KL6781 27 Version: 2.0.0
Input data (response from the Bus Terminal)
Byte 0: Status byte Byte 1: DataIN1, high byte Byte 2: DataIN1, low byte
0xA0 (1010 0000
bin
) 0xXX 0xXX
Explanation:
• The terminal returns a value as a receipt in the status byte that differs only in bit 0.6 from the value of
the control byte.
• The input data word (byte 1 and byte 2) is of no importance after the write access. Any values still
displayed are invalid!
IV. Read Register 32 (check changed feature register)
Output Data
Byte 0: Control byte Byte 1: DataOUT1, high byte Byte 2: DataOUT1, low byte
0xA0 (1010 0000
bin
) 0xXX 0xXX
Explanation:
• Bit 0.7 set means: Register communication switched on.
• Bit 0.6 not set means: reading the register.
• Bits 0.5 to 0.0 indicate register number 32 with 10 0000
bin
.
• The output data word (byte 1 and byte 2) has no meaning during read access.
Input Data (answer of the bus terminal)
Byte 0: Status byte Byte 1: DataIN1, high byte Byte 2: DataIN1, low byte
0xA0 (1010 0000
bin
) 0x00 0x02
Explanation:
• The terminal returns the value of the control byte as a receipt in the status byte.
• The terminal returns the current value of the feature register in the input data word (byte 1 and byte 2).
V. Write Register 31 (reset code word)
Output Data
Byte 0: Control byte Byte 1: DataOUT1, high byte Byte 2: DataOUT1, low byte
0xDF (1101 1111
bin
) 0x00 0x00
Explanation:
• Bit 0.7 set means: Register communication switched on.
• Bit 0.6 set means: writing to the register.
• Bits 0.5 to 0.0 specify the register number 31 with 01 1111
bin
.
• The output data word (byte 1 and byte 2) contains 0x0000 for reactivating write protection.
Input Data (answer of the bus terminal)
Byte 0: Status byte Byte 1: DataIN1, high byte Byte 2: DataIN1, low byte
0x9F (1001 1111
bin
) 0xXX 0xXX
Explanation:
• The terminal returns a value as a receipt in the status byte that differs only in bit 0.6 from the value of
the control byte.
• The input data word (byte 1 and byte 2) is of no importance after the write access. Any values still
displayed are invalid!