read modbus register as ASCII

[qiuqiaoan]

hello,
i have modbus which have string valves as following example
modbus string valve example

and i set the modbus template in rapid scada as following
modbus template in rapid scada

set the value type in channels as ASCII text as following
value data to ASCII text

and simulate the value from modbus slave as following
simulating modbus slave value

but the display was wrong as following
wrong display in rapid scada

[manjey73]

leave the format as D, D.D, and so on. ASCII text is for another.

[Mikhail]

Hi,

1. Read the registers from 30215 to 30218 as a double (8 bytes) in Communicator. They will be passed to a one input channel.
2. Check the displayed value.

Share new screenshots, please.

[qiuqiaoan]

Hi, Mikhail
double (8bytes) worked. as shown in below link
read as double

if I would like to convert the 20 bytes ascii string (they are all numbers) to number, so the values can be stored in the database and be shown on the chart.
do you have suggestion for that, any tested formular?

thanks

[Mikhail]

Hi,

do you have suggestion for that, any tested formular?

You should develop a formula by yourself. The idea is the following:
1. Create an input channel of the calculated type.
2. Add a formula in the Formulas table

double MyFunc()
{
// your code here
}

3. Use this formula for the created input channel.

[Mikhail]

In the formula you should join the strings. Something like

string s = "";
for (int cnlNum = 101; cnlNum < 110; cnlNum++)
{
  s += ScadaUtils.DecodeAscii(Val(cnlNum));
}
return double.Parse(s)

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