Mini Thermal Printer doesn't accept printing parameter commands

My ‘mini thermal printer’ doesn’t seem to accept the ‘Control Parameter Commands’ described in section 5.2.9 of the manual on the product page.

Specifically, the sequences ‘ESC 7 n1 n2 n3’ and ‘DC2 # n’ do not have the expected effect (changing the print speed/density), and the printer prints out ASCII characters corresponding to whatever values I used for n1, n2, n3 etc.

Are pimoroni able to provide a reference for the command set actually supported by this printer?

The firmware version printed by the self-test is “GV2.16.08 20180627_R”.

Same for me, see my Post for a picture.

Did you get any Information?
Or did you send back the printer ?

Hi. I’m disappointed to say that I haven’t had any information from pimoroni about this.

For my own purposes, I’ve found that with a good ~4A 5V supply, the printer works well and I haven’t worried about the missing commands. I guess it’s possible that the manufacturer has removed the configuration command (possibly because they think they’ve perfected auto compensation)…

I did try using a hefty 9V supply as well, but this caused the paper to feed so quickly that the print head had trouble keeping up and the density was much lower.


I contacted Pimoroni support via Mail an got a solution, my first unit seems to be defective.
See: Mini Thermal Printer missing pixels dull printing
Perhaps Pirmoroni would accept a replace in your case too due to the posting in this forum ?