View source for Active Video Line (MSB) Register

{{NextRegister
|Number=$1E
|Readable=Yes
|Writable=No
|ShortDesc=Holds the MSB (only, as bit 0) of the raster line currently being drawn.
}}
The low 8 bit part of the raster line number is in {{NextRegNo|$1F}}.

The line coordinates use coordinate system of [https://gitlab.com/thesmog358/tbblue/blob/master/docs/extra-hw/copper/COPPER-v0.1c.TXT Copper coprocessor], i.e. line 0 is the first line of pixels.