α2 Simple Application Controllers |
The Command String 7 |
7.4Communication Timing Chart
The communication time for α2 Series dedicated protocol is represented by the diagram below. The communication time is identical for Read and Write operations. Thus, only one diagram has been used to demonstrate the possible delaytimes for sending and receiving 8-bit binary messages.
7.4.1Read/Write Data from the Controller
Format B READ/WRITE operation
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STX |
ETX |
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Computer |
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Communication |
02H |
03H |
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Line |
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α2 Controller |
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STX |
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STX |
ETX |
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! |
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02H |
21H |
02H |
03H |
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T0 |
Tw |
T1 |
TP |
T2 |
Time Chart |
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Line |
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7.4.2Communication Time
The calculation performed below are a guide to the approximate communication timing for dedicated protocol.
T0,T1,T2 = 1/Baud Rate x No. of bits in 1 character x No. of Characters
= 1/9600 x [1 (Startbit) x 8 (datalength) x 0 (parity none) x 1 (stopbit] x No. of characters
TP = Process Time *1 maximum time of 2.5s
Tw = 5ms + maximum of 1 scan time maximum time of 2.5s
Note:
*1 Process Time - Represents the duration needed for the α2 Series Controller to process with either READING the intended device or WRITING to the intended devices specified in the Command String. 1scan time + 5ms is the minimum time used for the Process Time.
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