Hi.
Everything is done on the background with the library. You can take a look at the library in the following link and see the methods available. Including the .text method
https://github.com/RuiSantosdotme/ESP-MicroPython/blob/master/code/Others/OLED/ssd1306.py
The library we’re using doesn’t support other fonts or image.
There is another library by Adafruit that supports graphics (drawing shapes). But it is deprecated and I’m not sure if it is working or if it supports other fonts 🙁
https://github.com/adafruit/micropython-adafruit-gfx
I’m sorry that I can’t help much here.
Thank you for your interest in our projects.
Regards,
Sara

Thanks Sara.
I have found a way of doing fonts.. see:

• https://github.com/peterhinch/micropython-font-to-py/blob/master/writer/WRITER.md   (can display fonts on the SSD1306 OLED)
• https://github.com/peterhinch/micropython-nano-gui  (this adds more functionality, some graphics etc – although I have not yet got this working I’ll persist for a while to see if I can).  Edit:  Turns out nanogui.py relys on the micropython cmath library – which (according to the docs) is not available on the ESP8266).

Cheers
Tim

Hi Tim.
Thank you for sharing. I’ll have to take a look at those libraries, and maybe come up with a new tutorial in the next weeks.
Regards,
Sara

FYI – Here’s my initial demo code:

# Original source from RNTLabs MicroPython on ESP8266 book
# Then modified for font and graphics from: See https://github.com/peterhinch/micropython-nano-gui# *** However, turns out nanogui.py cant be used as it requires cmath lib which is not available on ESP8266 (see cmath docs) 
# So instead just use Writer - see https://github.com/peterhinch/micropython-font-to-py/blob/master/writer/WRITER.md
from machine import Pin, I2C import gc import ssd1306 
#ESP32 Pin assignment 
#i2c = I2C(-1, scl=Pin(22), sda=Pin(21)) 
# ESP8266 - Pin assignment 
i2c = I2C(-1, scl=Pin(5), sda=Pin(4)) 
oled_width = 128 
oled_height = 64 
gc.collect() 
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)
oled.text('Hello BOB6!', 0, 0)
oled.text('Hello, World 2!', 0, 10)
oled.show()
# This causes the error: Import Error: cannot import name Label
# *** Turns out nanogui.py cant be used as it requires cmath lib which is not available on ESP8266 (see cmath docs)
#from nanogui import Label, Dial, Pointer, refresh 
#refresh(oled) # Initialise and clear display.
from writer import Writer
import arial10 # Font
wri = Writer(oled, arial10, verbose=False)
#The following Writer example works
#wri = Writer(ssd, freesans20) # verbose = False to suppress console output
Writer.set_textpos(oled, 16, 0) # In case a previous test has altered this
wri.printstring('Sunday\n12 Aug 2018\n10.30am')
oled.show()

Hi Tim.
Thank you so much for sharing your code.
I’ll try it out soon.
Regards,
Sara

You’re welcome.
FYI – I eventually got his font-to-py generator working to. Had some issues – but turns out my ESP8266 needed rebooting.
Take a look at: https://github.com/peterhinch/micropython-font-to-py/blob/master/FONT_TO_PY.md 
I needed to use Linux to get it working.

Hi Tim. Once again thank you for sharing.
I definitely have to take a look at those examples.
Regards,
Sara