NFC card tracking collection of ideas

rtrbt commented 2 years ago

Use EVSE as RAM extension to keep track even if the ESP restarts
Track charged energy per card
Track charges per card; Timestamps? -> Requires NTP (#26)
Allow setting max charging current and 1p/3p per card
Have a master card that can not start, but can stop charges started by any other card
Generate reports? -> ESP does not have enough resources to generate PDFs but we could do this in web interface, i.e. in Javascript

Log all charges into a binary file: (Written when starting to charge)

NTP or RTC synced date: 4 byte unix timestamp in minutes or 0 if we don't know the date exactly
Meter reading: 4 byte float or 0 if WARP Smart
Card/User ID: 1 byte

(Written when finished)

Charge duration: 3 byte seconds (allows tracking a charge of up to 194 days)
Meter reading: 4 byte float or 0 if WARP Smart = 16 byte per record Layout choosen to write end data behind start data. Detection of an incomplete record by checking file length % 16

For simple reports: Read the binary file in chunks, translate to CSV on the fly and stream out with an HTTP chunked response.

jensstark commented 2 years ago

Reports? Generate CSV or similar to create accounting records. Running number, Tag ID, start time, end time, charged energy...

Retrievable via Web API, offering sample LibreCalc instructions to use.

Alestrix commented 2 years ago

Idea: Once 1p3p is possible (Energy Manager), allow setting 1p/3p per nfc tag

Tinkerforge / esp32-firmware