DC Power Supply
【
DC-10-D/DC-20-D/DC-10-DH/DC-20-DH
】
6. SERIAL Communication
-45-
6-3 Communication Message Packet
A communication message packet consists of four types of fields as follows.
• Header field:
(SOF, each address, c data field length information)
• Command field:
(See the command list to be described later.)
• Data field:
(A field for data to complement each command)
• Checksum:
(Command error check)
Details on each field are shown below.
Table 6-2
Message packet
Header Field
Command field
Data field
Checksum
1byte
・
SOF
・
Address
1byte
・
Data length
information
1byte
0x00
～
0xFF
0
～
7byte
Data transmitted in relation to
the command.
The length depends on the
command.
1byte
XOR values of all data
until just before.
●
Header field
The header field includes four pieces of information. A header consists of a data length of two
bytes in total. The first one bit is SOF, the following seven bits are the address, and the last eight
bits are information on the data field length, respectively.
Details on each piece of information included in a header are as follows:
○
SOF(Start of frame)
：
This is a specific bit patter which indicates the start of frame.
SOF is 1 bit and, when the bit takes 1 in power, the frame starts from there
and the following Address is analyzed.
○
Address
：
It becomes a 7-bit addressing signal.
For the power supply address setting, refer to [6-2. Address setting method
for network address setting].
The address range that can be set is from 1 to 127.
Communication is established only for units whose communication address
and power setting address match.
Also for the RS-232C or RS-485 communication, the Address set in power
needs to be transmitted.
○
Data field length
：
The total number of bytes of the c the data is transmitted.
The commands themselves are all 1byte but the following data are 0 to 7
bytes depending on the command.
The allocation is as follows.
0: 1byte (command only)
1: 2byte (command + -byte data length)
2
:
3byte
(command + 2byte data length)
・
・
7: 8byte
(command + 7byte data length)
For the data length of each command, refer to the command list in [Tables
6-4 and 6-5].
Summary of Contents for DC-10-D
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