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Delta Electronics Programmable Logic Controller DVP-PLC User Manual

Page 347

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7 Application Instructions API 50-99

D V P - P L C A P P L I C AT I O N M A N U A L

7-63

Remarks:

1. When this instruction is being executed, it will require 8 scans to obtain one valid keyed-in value. A scan period

that is too long or too short may result in poor keyed-in effect, which can be avoided by the following methods:

a) If the scan period is too short, I/O may not be able to respond in time, resulting in not being able to read the

keyed-in value correctly. In this case, please fix the scan time.

b) If the scan period is too long, the key may respond slowly. In this case, write this instruction into the time

interruption subroutine to fix the time for the execution of this instruction.

2. Functions

of

M1167:

a)

When M1167 = On, HKY instruction will be able to input the hexadecimal value of 0 ~ F.

b)

When M1167 = Off, HKY instruction will see A ~ F as function keys.

3. Functions of D1037 (only supports EH/EH2/SV series MPU):

Write D1037 to set the overlapping time for keys (unit: ms). The overlapping time will vary upon different program

scan time and the settings in D1037.