The internal data memory of the myDatalogEASY IoTmini is designed as a circular buffer with 8 sectors. If the
entire memory (3MB ) is full, the sector with the oldest data is deleted fully before new data can be saved in
this sector again. This means that the internal data memory comprises at least 2,625 MB of valid data and a
maximum of 3MB .
For this reason, it is recommended to coordinate the data transmission and record interval in such a way that
a maximum of 2,625 MB has to be recorded between two transmissions. If it can be expected that individual
transmissions fail due to poor network coverage, this must also be taken into consideration when calculating
the data volume to be saved. Additionally, it must be noted that the system-related overhead is 10 Byte per
data record and that the first 8 Byte of each sector are reserved for the internal memory management. The 10
Byte overhead already includes the timestamp, so it does not have to be taken into account when calculating
the size of the entire record. If there is not enough free space in a sector to save the entire data record, the
data record is written to the next sector. This means that a data record is not written over the sector limits.
Note:
Additional explanation regarding the functionality of the circular buffer
Data memory after the first data is recorded:
Data memory once 3MB has been recorded
Data memory if further data is recorded once 3MB has already been recorded
Note:
Additional explanation on calculating the data volume to be saved:
To provide a clear and simple overview, the following example assumes that the sectors can only record two
complete data records.
1)
Free memory in sector 1 is not enough to record a full data record (ov data).
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