# | Value |
---|---|
0 | LSB of graphics window left column (ec) |
1 | MSB of graphics window left column (ic) |
2 | LSB of graphics window bottom row (ic) |
3 | MSB of graphics window bottom row (ic) |
4 | LSB of graphics window right column (ic) |
5 | MSB of graphics window right column (ic) |
6 | LSB of graphics window top row (ic) |
7 | MSB of graphics window top row (ic) |
8 | text window left column |
9 | text window bottom row |
10 | text window right column |
11 | text window top row |
12 | LSB of graphics origin x coordinate (ec) |
13 | MSB of graphics origin x coordinate (ec) |
14 | LSB of graphics origin y coordinate (ec) |
15 | MSB of graphics origin y coordinate (ec) |
These VDU variable numbers are different to the those of OS_ReadVDUVariables?, and that it can read many more variables. It should be used in preference to OS_Byte 160.
ic: Internal Co-ordinates. The origin is always the bottom left of the screen. One unit is one pixel wide and one pixel high.
ec: External Co-ordinates. A pixel is (1 \<\< XEigFactor)
units wide and (1 \<\< YEigFactor)
units high, where XEigFactor and YEigFactor are VDU variables.