Mini Thermal Printer QR701

Ich habe mir einen Mini Thermal Printer QR701 (EH48-20243)  aus China bestellt.
Der Printer druckt eine Testseite wenn man hinten auf der Platine den Schalter betätigt.

Mini Thermal Printer

Bei mir jedoch nicht….
Jetzt habe ich den Grund gefunden, ich habe ein zu schwaches Netzteil verwendet (1 A ).Mit einem stärkeren hat es funktioniert..

Noch ein Tipp:
Pinbelgeung beachten !
RX Pin ist Blau
TX Pin ist Grün
DTR Pin ist Gelb ( den unbedingt auf GND legen )

Hier noch einige Dokumente…
701print driver board –> pdf

701print driver board  –> word

Here is my sketch I used for testing:

I also make some modifications on the Adafruit_Thermal library.
(which is not any more needed if you are using the latest library version, see example form library)

It is basically the baud rate: –> Changed to 9600 !
diff Adafruit thermal printer lib

Latest Adafruit Library is on git hub

Check also a other blog about the Mini Thermal Printer:


15 Kommentare zu „Mini Thermal Printer QR701“

  1. hi, have you some problem with printer ? my printing chinese letters. I try modificattion library but its not work. Could you help me ?

    1. Mhh..
      –>Try to download the latest Adafruit Library from Github (link is in main thread).
      –>Use the example A_printertest.ino. In this example you are able to change the baud rate in the ino file.

      If this still isn’t working. I found in the documentation „701print driver board.pdf“ a command for cancel the chinise mode. The command is descripted on page 39 >> FS. << – use google translator to translate it.

      To test this, you have to modify the Adafruit_Thermal.h , make the method writeBytes(uint8_t a, uint8_t b) public.
      Then in the A_printertest.ino you should add after

      printer.begin(); // Init printer (same regardless of serial type)

      this new code:

      Don't know if this helps…

      1. the problem continues 😦
        Chinese print —>test

        please could send
        values or code
        circuit resistors:
        in my circuit board replaces the resistors logic SP3232EEN
        I will remove the circuit SP3232EEN

  2. The SP3232EEN is just a serial interface ic. So this will change nothing.
    That’s firmeware related.

    For me you have the Japanese Version of the Printer JP-QR701, instead of QR701, so standard mode is Japanese.
    So instead of sending the command FS. (chinise mode off), maybe you have to send the command FS& (printer.writeBytes(28,38);) which would be chinise mode On command. So maybe negative logic…

    Otherwise ask also your seller for technical information.

  3. „To test this, you have to modify the Adafruit_Thermal.h , make the method writeBytes(uint8_t a, uint8_t b) public.“
    like you wrote in up comments
    but I managed to find it
    but it’s still not working
    are you still using QR701?
    I’m on the edge of surrender, just second week of struggle
    could you send me your changed Adafruit library on my email?
    what do I have to do with bitmaps to make it work?

    My situation is: I tried adafruit arduino and CUPS on rasberry pi.
    Arduino works the best because I can print all kind of text big and small, bolded etc.
    but when it comes to the bitmap it is printing error random characters
    first it was chineese then I managed to change the coding to UTF-8 and now it’s random letters
    please help!
    all the best

  4. This printer is slightly different from the one sold by Adafruit or Sparkfun. Mine seemed to have Chinese character mode turned on by default. And it only printed Chinese.

    From what I understood from the Chinese data sheet posted here (with the help of Google Translate) the Chinese mode could be switched off with printer command „FS .“ or „28 46“ in decimal (page 34).

    I could make my qr701 work with Raspberry Pi and Adafruit_Thermal library by modifying the library’s __init__ method to include the following command: self.writeBytes(28, 46). Just put it somewhere in the end of the method. This solved it for me. The printer occasionally prints a page in Chinese but then reverts to normal. I have yet to understand why it does that.

    Now another problem I had was that the printer did not want to print Russian characters (I am Russian). So I had to force it to use another code page with command self.writeBytes(27, 116, 7) where 7 is the number of the code page with Cyrillic characters from the data sheet (page 45).

    Hope this helps. Or it least gives clue where to look for an answer. Cheers, fellow makers.

  5. With this printer you need to convert TTL to rs232 with a ci or with two transistor, that’s the reason it’s printing gibberish, the level are different and inverted between two standards …

Kommentar verfassen

Trage deine Daten unten ein oder klicke ein Icon um dich einzuloggen:

Du kommentierst mit Deinem Abmelden /  Ändern )

Google+ Foto

Du kommentierst mit Deinem Google+-Konto. Abmelden /  Ändern )


Du kommentierst mit Deinem Twitter-Konto. Abmelden /  Ändern )


Du kommentierst mit Deinem Facebook-Konto. Abmelden /  Ändern )

Verbinde mit %s