Delta Electronics DeviceNet Slave Communication Module IFD9502, Руководство по применению

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DeviceNet Slave Communication Module IFD9502
DVP-PLC Application Manual 11
z Common Services
Implemented for
Service code
Class Instance
Service name
0x32 No Yes Read PLC data
0x33 No Yes Write PLC data
3. Format of inquiries and messages responded
z IFD9502 allows you to inquire PLC by explicit messages. The format of inquiry is shown in the
table below.
Byte position Data read from PLC Data written into PLC
0 Frag [0]+XID+MAC ID Frag [0]+XID+MAC ID
1 R/R [0]+Service code [0x32] R/R [0]+Service code [0x33]
2 Class ID [0x96] Class ID [0x96]
3 Instance ID Instance ID
4 Position address LSB Position Address LSB
5 Position address MSB Position Address MSB
6 Number LSB Service data LSB
7 Number MSB Service data MSB
z
Explanation
„ “Position address” refers to the No. of the device in the register of PLC. For example, the
position address of M0 is 0 and that of D100 is 100.
„ “Number” refers to the number of PLCs. When the read device is a word device, “Number”
refers to the number of words read; when the read device is a bit device, “Number” refers to
the number of bits read.
„ Bit devices, S, X, Y and M in DVP-PLC allow the reading of maximum 16 bits and writing in
of only 1 bit (either 0 or 1). Devices T, C and D in DVP-PLC allow the reading of maximum 3
words and writing in of 1 word. See the table below.
Device in PLC Max. length to be read allowed Max. length to be written in allowed
S 16 bits 1 bit
X 16 bits Not support
Y 16 bits 1 bit
M 16 bits 1 bit
T (bit device) 16 bits 1 bit
C (bit device) 16 bits 1 bit
T (word device) 3 words 1 word
C (word device) 3 words 1 word
D (word device) 3 words 1 word