Salicru CV30, Руководство пользователя, Страница: 104 / 140

104 - 140 Communication protocol
7.2.3 ASCII mode
Name Definition
Coding
system
Communication protocol belongs to hexadecimal system. The meaning of message character in ASCII:
“0”…“9”, “A”…”F”, each hex is represented by the ASCII message corresponds to the character.
Character ‘0’ ‘1’ ‘2’ ‘3’ ‘4’ ‘5’ ‘6’ ‘7’
ASCII CODE 0x30 0x31 0x32 0x33 0x34 0x35 0x36 0x37
Character ‘8’ ‘9’ ‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘F’
ASCII CODE 0x38 0x39 0x41 0x42 0x43 0x44 0x45 0x46
Data
format
Starting bit, 7/8 data bit, check bit and stop bit. The data formats are listed as below:
11-bit character frame:
Starting
bit
BIT1 BIT2 BIT3 BIT4 BIT5 BIT6 BIT7 BIT8
Check
bit
Stop
bit
10-bit character frame:
Starting
bit
BIT1 BIT2 BIT3 BIT4 BIT5 BIT6 BIT7 Check bit Stop bit
In ASCII mode, the frame header is “:” (“0*3A”), frame end is “CRLF” (“0*0D” “0*0A”) by default. In ASCII mode, all the
data bytes, except for the frame header and frame end, are transmitted in ASCII code mode, in which four high bit
groups will be sent out first and then, four low bit groups will be sent out. In ASCII mode, the data length is 8 bit. As for
‘A’~‘F’, its capital letters is adopted for ASCII code. The data now adopts LRC checkout which covers slave address to
data information. The checksum equals to the complement of the character sum of all the participated checkout data.
Standard structure of ASCII frame:
START ‘:’ (0x3A)
Address Hi
Communication address:
8-bit address is formed by the combination of two ASCII codes
Address Lo
Function Hi
Function code:
8-bit address is formed by the combination of two ASCII codes Function Lo
DATA
（
N-1
）
…
DATA
（
0
）
Data content:
nx8-bit data content is formed by combination of 2n (n ≤ 16) ASCII codes
LRC CHK Hi LRC check code: