NEC X754HB, Manual

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12. Serial No. & Model Name Read
12.1 Serial No. Read
This command is used in order to read a serial number.
1) The controller requests the monitor to read a serial number.
Header Message Check code Delimiter
SOH-'0'-Monitor ID-
'0'-'A'-'0'-'6'
STX-'C'-'2'-'1'-'6'-ETX BCC CR
Header
SOH (01h): Start of Header
'0' (30h): Reserved
Monitor ID: Specify the Monitor ID which you want to get serial number.
Ex.) If Monitor ID is '1', specify 'A'.
'0' (30h): Message sender is the controller.
'A' (41h): Message type is "Command".
'0'-'6'(30h, 36h): Message length
Message
STX (02h): Start of Message
'C'-'2'-'1'-'6' (43h, 32h, 31h, 36h): Serial No. command
ETX (03h): End of Message
Check code
BCC: Block Check Code
Refer to the section 4.3 “Check code” for a BCC calculation.
Delimiter
CR (0Dh): End of packet
2) The monitor replies the serial No. data to the controller.
Header Message Check code Delimiter
SOH-'0'-'0'-Monitor ID-
'B'-N-N
STX-'C'-'3'-'1'-'6'-
Data(0)-Data(1)---Data(n)-ETX
BCC CR
Header
SOH (01h): Start of Header
'0' (30h): Reserved
'0' (30h): Message receiver is the controller.
Monitor ID: Indicate a replying Monitor ID.
Ex.) When this byte is set to 'A', the replying Monitor ID is '1'.
'B' (42h): Message type is "Command reply".
N-N: Message length
Note.) The maximum data length that can be returned from the monitor at a time is
32bytes.
Ex.) The byte data 20h is encoded as ASCII characters '2' and '0' (32h and 30h).
Message
STX (02h): Start of Message
'C'-'3'-'1'-'6' (41h, 33h, 31h, 36h): Serial No. reply command
Data(0)-Data(1)----Data(n):Serial Number
Ø
The byte data 20h is encoded as ASCII characters '2' and '0' (32h and 30h).
Ex.) Foe example when receiveing Serial Number data 33h 31h 33h 32h 33h 33h 33h 34h
Step1: Serial Number data is encoded as character string.
Example:
33h 31h 33h 32h 33h 33h 33h 34h -> '3','1','3','2','3','3','3','4'
Step2: Decode pairs of ASCII characters to hexadecimal values.
Example:
'3','1','3','2','3','3','3','4' -> 31h 32h 33h 34h
Step3: Byte data represents the ASCII string data.
Example:
31h 32h 33h 34h -> "1234"
Result: Serial Number is "1234".