 bits control the number of bytes by which the VRAM address pointer
gets incremented upon a read or write (see table.)

<P><A NAME="Reg2116"></A><B><FONT FACE="Lucida Console">Register $2116/$2117:
VRAM Address (2b/W)</FONT></B>
<PRE>aaaaaaaa aaaaaaaa&nbsp; a: word address for accessing VRAM</PRE>
This register is used to set the initial address for a VRAM upload or download.&nbsp;
Multiply by two to get the byte address.&nbsp; Note that, since there is
only 64K of VRAM, the most significant bit must be set