Modbus Communication Rule For Ij Printer - Hitachi UX Twin Nozzle Instruction Manual

4.6 Modbus communication rule for IJ Printer

The Modbus communication rule for IJ printer is described. Please read them carefully and fully
understand and use the IJ printer.
(1) When IJ Printer is Offline, Offline/Online switching and Read Input Registers are only available.
In case of Read Holding Registers or Write Multiple/Single Register(s), please place IJ Printer
Online.
(2) When Holding Registers which overlap the plural functional classifications are read/written by
one communication message, it will NOT work correctly. If reading/writing operation of the
Registers overlaps their functional classification, please separate the message into plural
messages so that one message will NOT overlap plural functional classifications.
(3) When IJ Printer receives Modbus communication, IJ Printer will reflect the contents of the
message each time of communication. If plural writing operations are conducted, please use
Start/Stop control flag which are placed at the leading address of Holding Registers.
(4) Start/Stop control flag will be used when the data more than 247 bytes are written on Holding
Registers or when the writing operation is made on the Registers of which addresses are NOT
consecutive.
When the Start (0x0001) is written on Start/Stop control flag, the written data is held and there
will be NO writing operation onto Holding Registers.
When the Stop (0x0002) is written on Start/Stop control flag, all the data held on Holding
Registers will be reflected to IJ Printer.
(5) Character codes are the same as those which are used in Standard communication.
Please refer to Technical Manual, Section 5 Communication, for details.
In Modbus communication, Shift code characters and Time count characters can be also used
and communicated. They are shown in the table below.
Shift code character
Shift code start character
Shift code end character
(6) If the external signal was input for Print Data Recall, etc. when Read Holding Registers was
conducted more than once, there is a possibility that the data before external signal input and the
data after external signal input are mixed and the read result would be an unexpected data.
Therefore, when Modbus communication and the external signals are used together, it is
recommended to control the input timing of the external signal so that they will NOT overlap.
0xF25B Time count character
0xF26B Time count start character
0xF27B Time count end character
39
0xF25C
0xF26C
0xF27C