Using Frames When Exchanging Data; What Are Frames - Mitsubishi MELSEC AJ65BT-R2 User Manual

7 USING FRAMES WHEN EXCHANGING DATA

7. USING FRAMES WHEN EXCHANGING DATA

7.1 What are frames?

Frames are data added to match the external device specifications when transmitting
and receiving data.
When data is transmitted using frames, the end and head of the transmission/reception
data can be judged easily.
A program for adding the frame does not need to be created by the user when
transmitting, so the program can be simplified.
The R2 has the following two types of frames. A statement can be transmitted and
received by designating the registration No. of the default registration frame and user
registration frame.
Frame type
•
Frame preregistered in R2.
Default
registration •
The contents of the frame
frame
cannot be changed.
•
Frame in which random
character string is registered
by user into R2 EEPROM.
User registration
•
Up to 200 frames can be
frame
registered.
•
The contents of the frame
can be changed.
*1 Note that this is not the R2 buffer memory address.
R2 adds frame
Frame
R2
Registration
Outline
frame No. *
01 to FE
H
(1 to 254)
100 to 161
H
(256 to 353)
3E8 to 4AF
H
(1000 to 1199)
Frame Random data Frame
R2 adds frame
7 - 1
Frame contents
1
The data for codes 01 to FE
H
H
corresponding to the registration No. is
registered as one byte.
The arrangement of the data handled
by the external device, and data
H
assuming special characters are
registered.
Random character string (1 to 80
H
bytes) designated by user.
Frame
External device,
such as ID controller
MELSEC-A
Reference
,
H
Section 7.5.1
Section 7.5.2
7