Because it's controlling the VDU system, whereas the FRED/JIM/SHEILA OSBYTES are reading/writing the I/O.Using a VDU call to re-program the 6845 in a way that requires the user to specify the register and the value to set it to seems an odd choice. It does provide a mechanism to be able to do this from a tube processor, but there are also OSBYTE calls to read/write FRED, JIM and SHELIA.
Statistics: Posted by jgharston — Fri Jan 24, 2025 5:50 pm