INST.No.INE-863B KR2S
【
Communication Interface
】
Instruction Manual
-20-
7
MODBUS protocol
Caution
Make sure to read and understand this section to avoid any troubles.
1.
Requesting data immediately after power-on generates an error
The unit is always ready for communications and responsive to data request from PC. However,
after power-on, the unit does not respond normally until channel data becomes ready.
2.
As the control signal wire is not used, pay attention to retransmit a command.
The serial interface of this instrument communicates without using control wire.
Pay attention to retransmit a command as reception defects may occur depending on the status
of this instrument.
3.
Do not remove any devices or communication cables and do not turn ON or OFF the power supply
during communications.
If devices or cables configuring the serial interface are removed or if the power is turned ON
(OFF) during communications, the communications may stop or an error may occur. If this
happens, reset all the devices configuring the serial interface and restart the communications
from the beginning.
4.
Transmit the next command after confirming that the communication drive is switched OFF.
In RS-485, if multiple instruments are connected to same communications line, then only 1
instrument, of which instrument number is specified from the PC, drives the communications
line. At that time, for transmitting all the characters to the PC completely, the drive of the
communications line is turned OFF with some time interval after the last character is sent. If
the PC transmits a command to the next instrument before it becomes OFF, then the signal
crashes and normal communications cannot be done. Therefore take care when a high speed PC
is used. This interval is around 5ms.
!
Summary of Contents for KR2S
Page 2: ...INST No INE 863B KR2S Communication Interface Instruction Manual ...
Page 124: ...INST No INE 863B KR2S Communication Interface Instruction Manual ...
Page 125: ...INST No INE 863B KR2S Communication Interface Instruction Manual ...
Page 126: ...INST No INE 863B KR2S Communication Interface Instruction Manual ...
Page 127: ...INST No INE 863B KR2S Communication Interface Instruction Manual ...