Thermal Printing Setup (Raspberry Pi 3 Paspbian Stretch)

Question

I am using an Adafruit Thermal Printer TTL, if not Tiny, then Mini. I have tried following this tutorial and other tutorials like this one. As for the first tutorial, I am not sure if I should still change the /boot/cmdline.txt

the tutorial says that I should change

dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 rootwait

to

dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 rootwait

but my cmdline.txt is like this,

dwc_otg.lpm_enable=0 console=tty1 root=PARTUUID=9cd9d170-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles

should I still change it? I tried to follow the tutorial and changed it and came with this another problem, the tutorial says that I should change my etc/inittab file and remove the following lines

#2:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100

but there is no etc/inittab file anymore. I tried looking for a solution for this but I haven't found one. So I looked for another tutorial that does not involve messing with cmdline or the inittab file and found this

I tried connecting using the USB Port and tried test printing

echo -e "This is a test.\\n\\n\\n" > /dev/ttyUSB0

but it says that ttyUSB0 does not exist

So I tried printing using TTL,

it still does not print at all.

stty -F /dev/serial0 19200
echo -e "This is a test.\\n\\n\\n" > /dev/serial0

It says that serial0 is not there so I changed it to ttyAMA0, but when I proceed with the echo, it doesn't print at all. I also tried changing the baudrate, still no luck. Please help me. I have tried looking for Thermal Printer setup with Raspbian Stretch or Rpi3 but haven't found any.

All Thermal Printing Tutorials are from years ago and I know something has changed with the steps but I don't know where.

Answer 1

I don't know whether the problem is from the ports; however, it seems like you are just trying the random ports like /dev/ttyUSB0, /dev/serial0, ttyAMA0. May I suggest checking the correct port by this;

ls /dev/tty*

Run this while it is not connected, then check it while it is connected. Find the new port name and try codes above with it.

Answer 2

I got it working, the problem was the power source haha. The power source that I am using is 5v 500mA, when I changed it to 5v 2A, it worked just fine with the TTL connection.