Question about the Nokia 5110 84X48 display

I have a few questions for those of you familiar with the Nokia 5110 84X48 display.

I've used it in conjunction with the Adafruit libraries -

I know when you use one of the graphics primitive from the GFX library,for instance:
display.drawPixel(10, 10, BLACK);

the pixel is written to the buffer only, until you use a command like this:

at which point the pixel is written to the screen.

I also understand that since this is a SPI device, the library must set the CS pin of the SPI screen being communicated with to LOW to enable transmission. (or it might be high or some other state. not really sure)

Anyway, I have a couple of questions.

  1. Where is the screen buffer? Is it located on the Nokia 5110 board somewhere, or is it stored on the Arduino?
  2. Does the Adafruit library enable and disable the CS pin for the display each time a command is issued, or does the pin stay enabled once the init command is issued? I'm curious because I would like to drive multiple LCD's from one Arduino.

For instance, I define two screens, leftScreen and right Screen, and set all pins the same in the setup, except for the CS pin

In the body of the code would I be able to do something like this:


I hope my questions make sense. I'm going to give this a shot later tonight, but if any of you have some input now it could probably save me a little time and frustration. :slight_smile: