Mitsubishi Electric FR-V500 Instruction Manual page 142

7) Sum check code
The sum check code is 2-digit ASCII (hexadecimal) representing the lower 1 byte (8 bits) of the sum (binary)
derived from the checked ASCII data.
(Example 1)
Computer Inverter
ASCII code
* : When the Pr. 123 "waiting time setting" setting is other than 9999, create the communication request
data without "waiting time" in the data format. (The number of characters decreases by 1.)
(Example 2)
Inverter Computer
ASCII code
8) Error code
If any error is found in the data received by the inverter, its definition is sent back to the computer together with
the NAK code. (Refer to page 137.)
CAUTION
1. When the data from the computer has an error, the inverter does not accept that data.
2. All data communication, e.g. run command or monitoring, are started when the computer gives a
communication request. The inverter does not return any data without the computer's request. For
monitoring, etc. therefore, design the program to cause the computer to provide a data read request
as required.
Communication functions (Pr. 117 to Pr. 124, Pr. 342)
*
Station Instruction
Waiting
ENQ
number code
time
0 1 E 1
1
H05 H30 H31 H45 H31 H31 H30 H37 H41 H44 H46 H34
H H H H H H H
+ + + + + +
30 31 45 31 31 30 37
H
= 1F4
Sum
Station
STX Read data
number
0 1 1 7 7
H02 H30 H31 H31 H37 H37 H30 H03 H33 H30
H H H H H H
+ + + + +
30 31 31 37 37 30
H
= 130
Sum
133
Sum check
Data
code
0 7 A D F 4 Binary code
H H
+ +
41 44
Sum check
ETX
code
0 3 0
Binary code
3