Delta DVP-ES2/EX2/SS2/SA2/SX2/SE manual Program Example 2 COM2 RS-485, Bit mode

DVP-ES2/EX2/SS2/SA2/SX2/SE Operation Manual - Programming

3.When data receiving is completed, M1123 will automatically be ON. When data processing on the received data is completed, M1123 has to be reset (OFF) and the PLC will be ready for communication again. However, DO NOT continuously execute RST M1123, i.e. it is

suggested to connect the RST M1123 instruction after the drive contact M1123.

M1002		H86	D1120	Set up communication protocol as
	MOV
				9600, 7, E, 1
	SET	M1120	Retain communication protocol
	MOV	K100	D1129 Set up communication time-out as 100ms
Pulses for
sending request

Pulse

X0

Write transmitting data in advance

SET M1122 Sending request

	RS	D100	K10	D120	K10
Receiving
completed
	Processing received data
M1123		M1123	Reset M1123
	RST

Program Example 2: COM2 RS-485

Switching between 8-bit mode (M1161 = ON) and 16-bit mode (M1161 = OFF)

8-bit mode:

1.STX (Start of Text) and ETX (End of text) are set up by M1126 and M1130 together with D1124~D1126. When PLC executed RS instruction, STX and ETX will be sent out automatically.

2.When M1161 = ON, only the low byte (lower 8 bits) is valid for data communication, i.e. high byte will be ignored and low byte will be received and transmitted.

M1000

M1161

X0

RS D100 K4 D120 K7

Sending data: (PLC -> external equipment)

STX D100L D101L D102L D103L ETX1 ETX2

source data register, starting from the lower 8 bits of D100

length = 4

3 - 204