CaChars
Graphics mode console I/O for the TRS-80 Color Computer
...All operation of the BASIC interpreter works naturally.
It is developed in 6809 assembly language. It may be assembled with LWTOOLS (http://lwtools.projects.l-w.ca) under Linux, or with Windows cross-assemblers such as Chet Simpson's CASM which is included in RainbowIDE.
In order to build a disk image, you will also need the Toolshed utility suite. (http://sourceforge.net/projects/toolshed) - Earlier versions of CaChars used the imgtool utility that is a part of MESS, the Multi Emulator Super System.