printer.feedRows(1) prints 'J' in stead of a row feed, unknown firmware version

[ChrisIdema]

printer.feedRows(1); prints a J in stead of a row feed.
I suspected my firmware version is older, however I don't know the firmware version. Setting PRINTER_FIRMWARE in Adafruit_Thermal.h to 0 didn't change the behavior! That is strange, because it should print new-lines in case of older versions that don't support the row-feed command.
I changed the header files in both these locations:

• /home/USER/.arduino15/staging/libraries/Adafruit_Thermal_Printer_Library-1.2.0.zip
• /home/USER/Arduino/libraries/Adafruit_Thermal_Printer_Library

I added the following lines in my code as a sanity check:

#if PRINTER_FIRMWARE >=268
#error "PRINTER_FIRMWARE>=268"
#endif

It gives the error when I don't edit the header file and doesn't when I set it to 0. So that means it should be compiled using that define. I deleted the cache folder and restarted arduino ide several times. But it still prints J

I use printer #597.
This is what the sticker says:

Model: CSN-A2
S/N Z1912110420

The test page printed by the printer doesn't have a firmware version number. This is what I see:

Selftest
System: A2
Version: GV.16.08 20190822_R
[...]
MAX dots:80
Heat time:774
[...]
Selftest Finished

I have ubuntu 20.
I use esp32 DOIT devkit.
Printing text works well.
Printing bitmaps works well too, but I do see thin horizontal white lines through the image even after setting heating time to 255.

[xMase]

the problem is this command(comment the line to test) which is not interpreted by our firmware.
it would be good and right if they put the correct datasheet for our firmware and accept this pull request #30 for esp devices .

[caternuson]

Does commenting out that command fix the issue? Also not sure how #30 relates to this issue?

[caternuson]

Hopefully #46 fixes this. Simply removed that offending command. If that doesn't fix it, please comment and we can reopen.