Magnolia Microsystems provided several hardware enhancements for the H89. This included new disk controllers and extra memory. They offered support files and complete operating systems tailored for their hardware.
- CP/M 2.23
- CP/M 2.24
- CP/M Plus
- 128k RAM Board - Test Utility and 'Invisible Disk' for both MMS and Heath/Zenith CP/M
- Corvus Interface - Support for MMS CP/M
- Z-37 Controller - Support for MMS CP/M (not positive on content)