This manual describes the DDB (Direct Data Bus) function used to realize data input/output with a
CNC while running a program developed with the user PLC ladder language.
DDB includes the synchronous type (DDBS) and the asynchronous type (DDBA), but only the
asynchronous type will be explained in this manual.
DDB is a function that allows the PLC to directly read and write the various data in the CNC. By
setting the information required for reading and writing into the buffer and calling out the DDB function,
he PLC can set (write) the designated data into the CNC. Generally, the data is read and written in
one piece units, but data related to the control axis can be processed for the designated number of
axes.
Features of this function include that the read data can be referred to in the step immediately following
he execution of the DDBA command. This also applies to the written data.
(Note 1) Note that for the parameters, they may not be valid immediately after writing.
(Note 2) Even for the parameters that will be valid immediately after writing, displaying the screen
again may be required in order to reflect changes to the data displayed on the screen.
(Note 3) The functions related to the specifications not added to the NC cannot be used with the
DDB.
This manual is organized in the following manner after the first chapter. Please refer to the required
section for use.
6. Example of
DDB with
Ladder Circuit
5. Explanation of
Read/write
Data
4. Sub-section
No. List
3. Selection No.
List

2. Usage of DDB
Function with
ladder



编码器接头 MR-J3ENCBL5M-A2-L
直流电抗器 FR-HEL-H11K
直流电抗器 FR-HEL-H0.4K
直流电抗器 FR-HEL-H1.5K
可控硅输出模块 FX2N-16EYS
以太网模块 A1SJ71E71N-B5T
输入输出模块 FX2N-8ER-ES/UL
输出模块 A0J2-E24S
带以太网类型的Q系列CPU Q10UDEHCPU
DC 输入/晶体管输出模块 AJ65VBTCE32-32DT
PLC FX1S-14MT-ESS/UL
继电器输出单元 FX0N-40ER
弹簧夹端子台 Q6TE-18S
DC 输入/晶体管输出模块 AJ65VBTCE32-16DT
可控硅输出单元 FX2N-32ES
闪存卡 QD81MEM-4GBC
继电器输出模块 FX2N-8EYR
输出模块 AY82EP
晶体管输出模块 FX2N-8EYT
MES接口模块 QJ71MES96
输入输出模块 A0J2-E28DR
晶体管输出单元 FX2N-32ET
连接器 A6CON1E
PLC FX3U-16MT/ESS
串行通信单元 GT15-RS4-TE
输入输出模块 AX80Y14CEU
输出模块 AY60EP
网络模块 A1SJ71E71N-T
PLC FX2N-48MT-ESS/UL
端子排模块用电缆 AC10TB-E