DVP-ES2/EX2/SS2/SA2/SX2/SE Operation Manual - Programming
3-118
API Mnemonic Operands Function
50
REF P Refresh
Controllers
ES2/EX2 SS2 SA2
SE SX2
Bit Devices Word devices Program Steps Type
OP X Y M S K H KnX KnYKnM KnS T C D E F
D * *
n * *
REF, REFP: 5 steps
PULSE 16-bit 32-bit
ES2/EX2 SS2 SA2
SE SX2 ES2/EX2 SS2 SA2
SE SX2 ES2/EX2 SS2 SA2
SE SX2
Operands:
D: Start device for I/O refresh n: Number of devices for I/O refresh
Explanations:
1. PLC updates I/O status between END instruction and the start of next program scan. If an
immediate I/O refresh is needed, REF can be applied for performing I/O refresh immediately.
2. D can only be a multiple of 10, i.e. X0 or Y0, and the instruction is NOT applicable for I/O
points on DIO modules.
3. Only the I/O points on MPU can be specified for operand D for I/O refresh.
z When D specifies X0 and n ≦ 8, only X0~X7 will be refreshed. If n > 8, all I/O points on
MPU will be refreshed.
z When D specifies Y0 and n = 8, only Y0~X7 will be refreshed. If n > 8, all I/O points on
MPU will be refreshed.
z When D specifies X10 or Y10, I/O points on MPU except for X0~X7 or Y0~Y3 will all be
refreshed regardless of n value, i.e. only status of X0~X7 or Y0~Y3 remains.
4. For EX2/SX2 MPU only: If M1180 = ON and REF instruction executes, PLC will read the A/D
value and update the read value to D1110~D1113. If M1181 = ON and REF instruction
executes, PLC will output the D/A value in D1116 and D1117 immediately. When A/D or D/A
values are refreshed, PLC will reset M1180 or M1181 automatically.
5. Range for n (ES2/EX2): 4 ~ total I/O points on MPU. n should always be a multiple of 4.
6. Range for n (SS2/SA2/SE/SX2): 8 ~ total I/O points on MPU.
Program Example 1:
When X0 = ON, PLC will refresh the status of input points X0 ~ X7 immediately without delay.
X0 REF X0 K8
Program Example 2:
When X0 = ON, the 4 output signals on Y0 ~ Y3 will be sent to output terminals immediately before
the program proceeds to END instruction.