$dff006 is the vertical raster position register, $dff180 is the background color register, and $bfe001 is one of the registers belonging to one of the two CIAs of the Amiga; the piece of code copies 16 bits of data (on the amiga referred to as a "word") from $dff006 to $dff180, checks if bit 6 in $bfe001 is high - the bit that contains the status of the left mouse button of joy/mouse port #1 - and then branches back to the .loop label if the comparison resulted negatively - that is, if the bit was not high.
In plain-speak, it renders vertical green/blue/cyan gradients in the background until the left mouse button is pressed.
(as a side note, I spent 4-5 years coding on the Amiga in the early 90s.)
In plain-speak, it renders vertical green/blue/cyan gradients in the background until the left mouse button is pressed.
(as a side note, I spent 4-5 years coding on the Amiga in the early 90s.)