Delta Electronics Programmable Logic Controller DVP-PLC - Manual (Page 408)

8 Application Instructions API 100-149
DVP-PLC Application Manual 8-6
API Mnemonic Operands Function
101 MODWR Write Modbus Data
Controllers
ES/EX/SS SA/SX/SC EH/SV
Bit Devices Word Devices Program Steps Type
OP X Y M S K H KnX KnY KnM KnS T C D E F
S
1
* * *
S
2
* * *
n * * *
MODWR: 7 steps
PULSE 16-bit 32-bit
ES EX SS SA SX SC EH SV ES EX SS SA SX SC EH SV ES EX SS SA SX SC EH SV
Operands:
S
1
: Address of communication device S
2
: Address of data to be read n: Data to be written
Explanations:
1. Range of S
1
: K0 ~ K254
2. See the specifications of each model for their range of use.
3. ES/EX/SS series MPU does not support E, F index register modification.
4. Flags: See API 80 RS for explanations on M1120 ~ M1131, M1140 ~ M1143
5. MODWR is a drive instruction exclusively for peripheral communication equipment in MODBUS ASCII
mode/RTU mode. The built-in RS-485 communication ports in Delta VFD drives (except for VFD-A series) are
all compatible with MODBUS communication format. MODRD can be used for controlling communication (write
data) of Delta drives.
6. If the address of S
2
is illegal to the designed communication device, the device will respond with an error, PLC
will records the error code in D1130 and M1140 will be On. For example, if 8000H is illegal to VFD-S, M1141
will be On and D1130 = 2. For error codes, see the user manual of VFD-S.
7. The feedback (returned) data from the peripheral equipment will be stored in D1070 ~ D1076. After receiving
the feedback data is completed, PLC will auto-check if all data are correct. If there is an error, M1140 will be
On.
8. After M1140 or M1141 turn On, the program will send a correct datum to the peripheral equipment. If the
feedback datum is correct, M1140 and M1141 will be reset.
Program Example 1:
Communication between PLC and VFD-S series AC motor drives (ASCII Mode, M1143 = Off)