Eurotech PCN-1001, Руководство пользователя

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Test an RS485 connection and use the RS485_GUI PCN-1001 User manual
90
PCN-1001_UserMan_En_4.0
Example 1: setting the LED intensity to 100
In this case the Data is composed by the SLED command, the string terminator, and an argument (an unsigned
char parameter, 8 bits long):
COMMAND
STRING TERMINATOR ARGUMENT
Sled 0 100
The complete message is:
SNP PACKAGE
VALUE
Preamble 0xFF
Preamble 0xFF
Preamble
0xFF
Preamble 0xFF
Preamble 0xFF
SOH 0x01
Source 0x01
Destination 0x02
TotalPacketNumber 0x01
PacketNumber
0x01
DataLength 0x06
0x00
Data
Command “sled” 0x73(s)
0x6C(l)
0x65I
0x64(d)
String terminator 0x00
Argument (value = 100) 0x64
CRC16 CRC value = -27888 0x10
0x93
Postamble 0xFF
The slave will reply to this command with:
COMMAND
STRING TERMINATOR
“sled” 0
Example 2: requesting the kernel version installed in the PCN-1001
Example of request
COMMAND
STRING TERMINATOR
“ker_version” 0
This command does not need any parameter.
The Slave will answer with:
COMMAND
STRING TERMINATOR ARGUMENTS
“ker_version” 0 “2.1”
In this case, the parameter in the answer of the slave will be a string containing the kernel version.