LRF-3000P Ultrasonic flowmeter
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Annotations:
1.
(cr) indicates ENTER, its ASCII code value is ODH. (If) indicates changing a line and its ASCII code value is
OAH.
2.
“d” indicates 0~9 digits and 0 is expressed by + 0.0 00.
3.
“d” indicates 0~9 digits and the integral part has no decimal point.
4.
dddddddd indicates the electronic serial number of the machine.
5.
Character P could be added before every basic command, it indicates the feedback data has CRC check.
The check sum is obtained through binary addition, which is a cumsum binary system taking the least
8-bit binary data.
For example: Feedback information RT(cr)(lf): +10m3(cr)(lf)(corresponding binary data are 2BH,
31H, 32H, 33H, 34H, 35H, 36H, 37H, 45H, 2BH, 30H, 6DH, 33H, 20H, 0DH, 0AH ) sum data returned =2BH +
31H + 32H+ 33H + 34H + 35H+ 36H + 37H+45H + 2BH + 30H + 6DH + 33H + 20H = 2F7, and the least 8-bit
binary is F7.
Therefore, data of command PRT(cr)(lf) is + 12 0m3!F7(cr)(lf), "!" as for the delimiter, the first
part is the character for summation and the second part is an 1-bit check code.
6.
Use of W prefix: W+digit string address code+basic command, the digit string value range is 0~255,
divided by 13 (0DH ENTER),10 (0AH changing a line). If you want to access to the transient flow velocity of
No. 123 flowmeter, you could send command W123DV (cr) (If), the corresponding binary codes are 57H,
31H, 32H, 33H, 44H, 56H, 0DH and 0AH; only the meters with the same network address and command
could have data feedbacks.
7.
W and P commands could be combined for use, for example, , which means the network
address it reads is the total value of No. 123 flowmeter, its feedback data are accumulated and checked.
