What have you tried ?
If your register values are floatbe you set that as the type in buffer parser.
The offset defines how many bytes to offset from the initial read register 16000
and since you have enough data in the buffer (because i see you are reading 12 registers)
you can convert many registers all at once and name them with the convenience of buffer-parser.
( One 32bit float value needs 2 x 16bit registers hence the offset 4 bytes)
read this post that better explains offset calculations (link)
Flow :
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Regarding storage solutions there are many databases and some very good nodes like sqlite, mysql, mongodb, influxdb. I use sqlite in my project with node-red-node-sqlite. its simple and lightweight.
