File:VMU.pdf

Summary

Official application developer's manual for the Visual Memory Unit.

• Tutorial Manual
• Specifications
• Hardware Manual
• Programing Manual
• VMU-BIOS Specifications
• Sound Development Specifications
• Simulator Manual

Limitations

Due to the fact the VMU features a built-in BIOS handling OS-specific tasks, the documentation is lacking in a few low-level places, such as hidden instructions and internal SFRs. These are areas that should not concern a typical application developer but are crucial for emulation.

Errors

• The first example for the DIV instruction stores the wrong value in the accumulator. It should be 0x79 instead of 0x78.
• There are also many places with typos, where a register bit is referenced as being "set to 0" and "reset to 0," when it should say "set to 1" or "reset to 0."
• The Instruction Code for LD d9 on page VMC-186 is incorrect.