The first thing you want to do is install WICReset and reset the waste ink counter with the trial key, only one use per printer.
It will reset the printer counter from 100% to 80% and we want the 0%.
Once you successfully reset your printer counter to 80%, go to %APPDATA%\wicreset\application.log on Windows or ~/.wicreset/application.log on Linux-based systems.
wicreset.py will parse a WICReset log file and try to get the values for your printer.
To do this, run python wicreset.py --json <path to log>, which will give you a model that you can add to models.json.
If the structure is different to other printer models, this may fail and you'll need to look through the logs manually.
In application.log, you have to search for something similar to this (in this case we are using the Epson XP-700 Series): RemoteControl::RESET_GUID RESET GUID: XP-700 Series 1061 KEY.
Just below this line, you should see a series of hexadecimal numbers.
We're interested in the hexadecimal numbers with REAL at the end of each line.
It should look like this: 7C 7C 10 00 28 00 42 BD 21 10 00 68 49 6A 63 6A 74 64 76 74.
Now we convert every single one of them to a decimal and then add dots between numbers.
They should look like this: 124.124.16.0.40.0.66.189.33.16.0.104.73.106.99.106.116.100.118.116.
Do this with every single one of them; there's about 10.
Once you have the converted lines, you will see that they have a format:
{eeprom_link}.124.124.16.0.{password}.66.189.33.{oid}.0.{value}.{eeprom_write}.
eeprom_link is always 1.3.6.1.4.1.1248.1.2.2.44.1.1.2.1.
The password is the two numbers next to 124.124.16.0. in this case is 40 and 0.
Then, we have the 66.189.33 and the oid (16) with a value (104) and the eeprom_write (73.106.99.106.116.100.118.116).
To create our model, start with the following template:
"EPSON YOURMODEL": {
"password": [, ],
"eeprom_link": "1.3.6.1.4.1.1248.1.2.2.44.1.1.2.1",
"eeprom_write": "",
"ink_levels": {},
"waste_inks": [
{"oids": [, ], "total": },
{"oids": [, ], "total": },
{"oids": [, ], "total": }
],
"maintenance_levels": [, ],
"unknown_oids": []
}
We need to calculate the totals for the waste ink counters.
One of the OIDs and values looks like this: 16.0.104 for the Epson XP-700, so the OID is 16 with a value of 104.
If we do that with every single of them:
16 = 104 (group #1)
17 = 26 (group #1)
6 = 0 (unknown)
52 = 94 (maintenance #1)
20 = 0 (group #3)
21 = 0 (group #3)
18 = 18 (group #2)
19 = 9 (group #2)
6 = 0 (unknown)
53 = 94 (maintenance #2)
237.1.0 (unknown format)
To group the waste ink counters requires a bit of guessing. They tend to be consecutive and in pairs, such as (16, 17), (18, 19) and (20, 21). Some models have an extra value for some counters, which is usually set to 0 by WICReset during the 80% trial reset.
Now we need to convert the value of group #1 in hexadecimal.
In this case, 104 = 0x68 and 26 = 0x1A.
Then, we need to concatenate them in reverse, like this: 0x1A68 = 6760.0 in decimal.
After using WICReset with the trial key, we know the percentage is 80%.
So, we take the value after concatenating the two hex values in reverse and use that to find the total:
(6760 / 80) * 100 = 8450.0
Maintenance levels are always set to 94, so the OIDs with value 94 are for maintenance.
All other OIDs (not waste ink or maintenance) are unknown.
After putting everything together, we have this:
"EPSON XP-700": {
"password": [40, 0],
"eeprom_link": "1.3.6.1.4.1.1248.1.2.2.44.1.1.2.1",
"eeprom_write": "73.106.99.106.116.100.118.116",
"ink_levels": {},
"waste_inks": [
{"oids": [16, 17], "total": 8450.0},
{"oids": [18, 19], "total": 2902.5},
{"oids": [20, 21], "total": null}
],
"maintenance_levels": [52, 53],
"unknown_oids": [6, 237]
}
Guide made by @j6ta :)