Additional Semigraphics modes By setting the SAM such that it believes it is displaying a full graphics mode, but leaving the VDG in Alphanumeric/Semigraphics 4 mode, it is possible to subdivide the character box into smaller pieces. This creates the "virtual" modes Semigraphics 8, 12, and 24. In these modes it was possible to mix bits and pieces of different text characters as well as Semigraphics 4 characters. These modes were an interesting curiosity but not widely used, as the Semigraphics 24-screen consumed 6144 bytes of memory. These modes were not implemented on the CoCo 3.
Additional Semigraphics modes By setting the SAM such that it believes it is displaying a full graphics mode but leaving the VDG in Alphanumeric/Semigraphics 4 mode it is possible to subdivide the character box into smaller pieces This creates the "virtual" modes Semigraphics 8 12 and 24 In these modes it was possible to mix bits and pieces of different text characters as well as Semigraphics 4 characters These modes were an interesting curiosity but not widely used as the Semigraphics 24-screen consumed 6144 bytes of memory These modes were not implemented on the CoCo 3