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model 2000 DeviceNet Module Manual (DN611/DN611A)
Chapter 4 Operating Procedures for the DN611 (Software)
4
4.4 User Function Block for Slave Data Input/Output
MREAD and MWRITE instructions are used for the S controller to access the input/
output data areas of the DN611, which store data to output to slave devices and input
data received from them. A sample of user function block for slave data input/output is
described in this section.
The user function block described here is a sample, and can be customized to make it
easier for the user. The internal descriptions of the user function block are given in
Appendix D. For the procedures for preparing and registe
ring user function blocks, see the Engineering Tool - Basics (6F8C0875) or the
Engineering Tool Online Manual.
The user function blocks explained in this section are scheduled to be registered in the
Engineering Tool Version 1.5 up.
4.4.1
Input/output data area batch access
(1) Function
This is to write output data from the area (WRITE_DT) provided for the controller in
the polling output data area and bit stroe outputt data area of the DN611. If the data
is for polling, specify a data size in the rangge of 1 to 128 words; if it is for bit strobe,
the data size is fixed at 4 words.
Input data is also copied from the polling/bit strobe input data area of the DN611 into
the area (READ_DT) provided by the S controller. Specify a data size in the range of
1 to 128 words.
(2) Diagrammatic representation (Function block)
DN_SLAVERW
CH
REQ
UNIT
SLOT
DONE
ERR
WRITE_DT
READ_DT
N_WPOL
N_RPOL
STATUS