Simple (should be) buffer parser question

[SkyMo]

Hi. I'm reading serial data and its a bunch of hex encoded numbers. For example I might get 30,44,30,33 which is 0x0D03 or 3,331. Seems like a simple matter for buffer parser but I cannot get it to work.

My simple example below gives me a confusing error message: ""RangeError: The value of "offset" is out of range. It must be >= 0 and <= 0. Received 4" How could it be greater and less than zero?

Here is my flow, seems pretty simple but it's got me confused.

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[Steve-Mcl]

The error is a bug (fixed in my dev copy) but its just a visual/status issue. The problem is you are asking buffer parser to create 4 32bit values out of 4 bytes (30,44,30,33). To generate 4 32bit values, your input buffer would need to be 16 bytes (32/8*4=16)

Your main issue is the buffer is essentially an ASCII string (30=0, 44=D, 30=0, 33=3)

In order to make sense of that, you need to first convert it to a hex string of 0d03 then you can use that to do the conversion

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[SkyMo]

That works perfect. Node-Red is amazing and the people on this forum are the best. Where else can you get an answer in 15 minutes on a Sunday morning that is spot on. Thanks again!!