Chino GT120 Series, Instruction Manual

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Address : Numbers by which the master discerns each slave.
Instrument number 0 to 94 (00H to 5EH) and Global address 95 (7FH)
The numbers (20H to 7EH) are used by giving 20H of bias, because 00H to 1FH
are used for control code.
95 (7FH) is called Global address , which is used when the same command
is sent to all the slaves connected. However, the response is not returned.
Sub address : 20H fixed
Command type : Code to discern Setting command (50H) and Reading command (20H)
Data item : Data classification of the command object
Composed of hexadecimal 4 digits (Refer to the Communication command table)
Data : The contents of data (setting value) depends on the setting command
Composed of hexadecimal 4 digits (Refer to the Communication command table)
Checksum : 2-character data to detect communication errors
Delimiter : Control code to represent the end of command
03H fixed
Error code : Represents an error type. Composed of hexadecimal 1 digit.
1 (31H)-----Non-existent command
2 (32H)-----Not used
3 (33H)-----Setting outside the setting range
4 (34H)-----Status unable to set (e.g. AT is performing)
5 (35H)-----During setting mode by keypad operation
5.3 Checksum calculation
Checksum is used to detect receiving errors in the command or data.
Set the program for the master side as well to calculate the checksum of the response
data from the slaves so that the communication errors can be checked.
The ASCII code (hexadecimal) which corresponds to the characters ranging from the address
to that before the checksum is converted to binary notation, and the total value is calculated.
The lower 2-digits of the total value are converted to 2’s complements and then to hexadecimal
number, that is, ASCII code for the checksum.
Checksum calculation example
Main setting value: 600 (0258H)
Address (instrument number): 0 (20H)
• 1’s complement: Make each bit of binary 0 and 1 reverse.
• 2’s complement: Add 1 to 1’s complement.
5.4 Contents of the command
Notes on the setting command and reading command
• Possible to set the setting value by setting command of the communication function
even if the setting value is locked.
• Although the options are not applied, setting the items for the options is possible by the setting
command, however, they will not function.
STX ETX
P 0 0 0 1 0 2 5 8
02H 20H 20H 50H 30H 30H 30H 31H 30H 32H 35H 38H 03H
[Characters above are represented by ASCII]
Checksum
Checksum calculation range
[e.g.]
E
45H 30H
0
20H
20H
50H
30H
30H
30H
31H
30H
32H
35H
38H 0010 0000
0010 0000
0101 0000
0011 0000
0011 0000
0011 0000
0011 0001
0011 0000
0011 0010
0011 0101
0011 1000
+
10 0010 0000
[Hexadecimal] [Binary]
1101 1111
1
+
1110 0000
E 0
45H
30H
[1's complement]
[2's complement]
[Hexadecimal]
[ASCII]
Checksum