This is the FM Voice Progammer Cartridge Software for the Yamaha CX5M Music Computer. It is boxed and complete with owners manual. Here's some info about the software...
 
Yamaha YRM‑102 Voicing Programme
 
The Yamaha YRM‑102 Voicing Programme is an essential sound‑design tool for the Yamaha CX‑series music computers, giving users deep, hands‑on control over Yamaha’s early FM synthesis technology. Released in 1983 as a ROM cartridge for the MSX platform, the YRM‑102 was designed specifically to unlock the full creative potential of Yamaha’s FM Sound Synthesizer units used in the CX5M system. 
Advanced FM Sound Editing: Allows users to modify the built‑in FM preset voices or create entirely new sounds from scratch using detailed FM operator parameters. 
Precise Control Interface: Voice data is displayed in real time on the screen as it is entered via the CX5M keyboard, with audio output available instantly for accurate sound monitoring.
Voice Storage & Recall: Custom voices can be saved to cassette tape or data memory cartridges for later use in composition and performance sessions. 
Integration with Yamaha Music Software: Created voices can be used with other Yamaha cartridges such as the YRM‑101 Music Composer and YRM‑104 Music Macro, forming a complete early digital music production environment. 
Hard Copy Output: Voice data and complete voice tables can be printed using an MSX‑compatible printer, making it easier to document and archive sound designs. 
Highly Collectable Vintage Software: Supplied on a ROM cartridge, the YRM‑102 is now a desirable item for collectors, FM synthesis enthusiasts, and retro‑music technologists. 
Whether you are restoring a Yamaha CX5M system, exploring classic FM synthesis techniques, or building an authentic vintage digital music setup, the Yamaha YRM‑102 Voicing Programme remains a foundational tool from the early days of computer‑based sound design.