NOTE :
1. This product has user programmable ‘Data Groups’ which each store preset user values. The groups are
named M0-M9 giving a total of 10 ‘Data Groups’. Each data group has a subset of 8 parameters at number 10-17.
And The ‘M0’ Data Group is the power-on default data group. M1 and M2 is the shortcut bring up data group.
M3-M9 are ordinary storage data groups. Each Data Group (M0-M9) start address is calculated by the following
formula: 0050H + (Data group number * 0010H).
For example, M3 Data Group has the starting address as follows: 0050H + (3 * 0010H) = 0080H.
2. Key lock function reading and writing value are 0 and 1, 0 represents not lock, 1 represents lock
3, Protection status reading value are 0-3, 0 represents good running, 1 represents OVP, 2 represents OCP, 3
represents OPP.
4, Constant voltage and constant current reading value are 0-1, 0 represents CV, 1 represents CV.
5, Control output function reading and writing value are 0-1, 0 represents close, 1 represents open.
6, Level of backlight rank reading and writing value is 0-5, 0 represents the darkest, 5 represents the brightest.
7, shortcut bringing up data groups function writing value are 0-9, after writing, all corresponding data group are
extracted.
1.4 Error-checking:
In RTU mode, messages include an error–checking field that is based on a Cyclical Redundancy Check (CRC)
method. The CRC field checks the contents of the entire message. It is applied regardless of any parity check
method used for the individual characters of the message.
CRC Calculation method:
The Cyclical Redundancy Check (CRC) field is two bytes, containing a 16-bit binary value. The CRC value is
calculated by the transmitting device, which appends the CRC to the message.
The receiving device recalculates a CRC during receipt of the message, and compares the calculated value to
the actual value it received in the CRC field. If the two values are not equal, an error results.
The CRC is started by first preloading a 16-bit register to all 1's. Then a process begins of applying successive
eight-bit bytes of the message to the current contents of the register. Only the eight bits of data in each character
are used for generating the CRC. Start and stop bits, and the parity bit, do not apply to the CRC.
During generation of the CRC, each eight-bit character is Exclusive ORed with the register contents. The result is
shifted in the direction of the least significant bit (LSB), with a zero filled into the most significant bit (MSB)
position.
The LSB is extracted and examined. If the LSB was a 1 then an Exclusive OR (XOR) of the register with a pre-
set, fixed value takes place. If the LSB was a 0, no Exclusive OR (XOR) takes place.
This process is repeated until eight shifts have been performed. After the last (eighth) shift, the next eight-bit
character is exclusive ORed with the register's current value, and the process repeats for eight more shifts as
described above. The final contents of the register, after all the characters of the message have been applied, is
the CRC value.
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