CLS

The CLS command is used to clear the screen and return the cursor to the upper left corner. In other words, CLS clears the screen, eliminating everything that was previously printed.

Before printing new data to the screen, it is often useful to use CLS to have a clean and tidy space. In combination with other instructions, CLS can be used to create simple animations by erasing and redrawing elements on the screen. It allows you to update the user interface without leaving traces of previous operations.

The CLS command is generally very fast to execute and can also be used in graphics mode to clear the entire drawing area. It also has the ability to set a default background color, if possible. The clearing occurs with respect to the selected mode, so it will be a "pixel by pixel" clearing (if in bitmap mode) or "tile by tile" (if in tile mode). In the second case, the value of the EMPTYTILE variable will be used, possibly overridden.

In the case of a graphical erasure, you can also indicate the coordinate from which to start erasing the screen as well as the size of the erasure (in terms of width and height). Particular attention must be paid to the fact that these metrics are relative to the limits of the underlying hardware: therefore, if a byte contains for example 4 pixels, the coordinates and dimensions will be "modulo 4".

EXAMPLE

 CLS
 CLS WHITE
 CLS 100, 100, 8, 8

Used in:
TEXT POSITIONING (USING LOCATE) TEXT POSITIONING (USING HOME)