Hi everyone !
I have a problem with a Socomec I31. It send me a DWord Signed on ModBus and I can't add the two Word for make a Decimal Value.
How I can read my S32 in decimal ?
Thank you !
Feed the value into a debug node and post the result here so we can see exactly what you have
Hi !
This is the result of my debug node :
Blockquote :
msg.payload : array[2]
array[2]
0: 65535
1: 65534
Thanks !
I should think you need something like
msg.payload = (msg.payload[0] << 16) + msg.payload[1]
return msg
Your code return me :
-2
which would be correct for a 32 bit signed int when passed that data.
In hex that is FFFFFFFE which is -2.
I create a function :
msg.payload=parseInt(msg.payload[0]+msg.payload[1] << 16);
return msg;
The message returned is : -3604480
With a Usigned 32 bits it's OK...
I don't understand what you are saying. What result are you trying to get?
In my test function :
msg.payload=(msg.payload[1] << 32)+msg.payload[0]
return msg;
In my simple add function :
msg.payload=parseInt(msg.payload[0]+msg.payload[1] << 16);
return msg;
You have not made it clear whether everything is now working as you expect. If not the what output are you expecting?
Sorry,
It does'nt work. I expected read 1 500w or even 2 000w...
Well the problem is not in the conversion. The value 0xfffffffe as a 32 bit signed integer is -2. Considering it as an unsigned integer gives a huge number.
Yeah, the MSB is : 65535, but, how do I read those two words correctly ?
I have found the solution.
For me, I read with this function :
msg.payload=(msg.payload[0])+(-msg.payload[1] << 32)
return msg;
And it's work !
In output, it's my value in decimal.
Thanks @Colin
Can you give an example of the data in and out for that formula, I would like to see why it works.
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