Thermal Printer library for arduino/esp32

Table of Contents

• Introduction
• Quick-start
• Features

Introduction

A printout exactly as you planned! I decided to create a more functional library than the popular Adafruit library. Less errors, easier start - just use! I will be grateful for feedback.

Created by BinaryWorlds @2019

Tested on firmware 2.69 and JP-QR701 Some features may not work on the older firmware.

Check the comments in TPrinter.h and TPrinter.cpp to learn more.

Quick start

Check examples.

1. Import library:

#include "TPrinter.h"
#include <HardwareSerial.h> // or SoftwareSerial

2. Set baudrate and pins.

const int printerBaudrate = 9600;  // or 19200 usually
const byte rxPin = 16;   // check datasheet of your board
const byte txPin = 17;   // check datasheet of your board
const byte dtrPin = 4;   // if used

3. Init

HardwareSerial mySerial(1);
Tprinter myPrinter(&mySerial, printerBaudrate);

void setup() {
  micros();
  mySerial.begin(printerBaudrate, SERIAL_8N1, rxPin, txPin);  // must be 8N1 mode
  myPrinter.begin();
}

Features

• Waiting for end of print process
• Change heating parametrs
• Print bitmap - scalable and centered

Waiting for end of print process

Mode, choose one:

1. By checking DTR pin If enabled and set wrong busyState - print will no start.

myPrinter.enableDtr(dtrPin, HIGH);   // pinNR, busyState - default LOW;

disableDtr(); // disable checking DTR pin

2. Calculate print time basing on current heating parametrs (default). Fast as DTR(similar time).

myPrinter.autoCalculate(true); // false - off

3. Set constant time as in Adafruif library (worst option). This mode is active, if DTR and autocalculate is disabled.

myPrinter.autoCalculate(false);  // turn off default mode

myPrinter.setTimes(30000, 3000);
// oneDotHeight_printTime, default: 30000,
// oneDotHeight_feedTime, default: 3000
// in micros

Change heating parametrs

myPrinter.setHeat(1, 224, 40);  // default: 0,255,0 called in begin

Best quality: the smallest number of dots burned, the longest heating time

• dots: default 9 (80dots) becouse (9+1)* 8; units: 8 dots;

• time: default 80 (800 us); units: 10 us

• interval: default 2 (20us); units: 10 us

  (default in printer)

Print bitmap - scalable and centered

printBitmap(*bitmap, width, height, scale = 1, center = true)

• bitmap - uint8_t array, each bit in byte - one printed dot(scale 1)
• width of bitmap - must be a multiple of 8 for example, if you try to print Adarfruit logo set width to 80. It's real size of this image. adalogo_data has 750 bytes length. 80 dots width * 75 dots height = 6000 dots 6000 dots / 8 = 750 bytes Each line in example have 5 white dots at right side. This is because the data is sent in bytes
• height of bitmap - real value, in above example - 75
• scale - default 1, if 0 or greater than the maximum possible scale - the image is printed at it's maximum size
• center - default true