found a bug on draw command

[boriel]

Unlike Sinclair Basic, which uses FLOAT type for every variable, when you don't declare vars, ZX BASIC tries to guess the best type for them.
It seems it's using Byte types (range -128..127) which could to be causing overflow.

Add this line:

Code:

11 DIM x1, x2, y1, y2 As Integer

to ensure the Integer type will be used (using Float will also work, but will take more memory and will be almost as slow as Sinclair BASIC).