Introduction to reverse-engineering vintage synth firmware
a day ago
- #embedded-systems
- #vintage-synths
- #reverse-engineering
- Introduction to reverse-engineering vintage synthesiser firmware, focusing on the Yamaha DX7.
- Target audience includes technical individuals new to reverse-engineering, 8-bit architectures, or embedded development.
- Basic knowledge of low-level programming, binary, and pointers is sufficient; no assembly language or specific processor architecture knowledge required.
- The process involves understanding the DX7's memory mapping, including peripheral devices like the LCD screen and sound chips.
- Address decoding logic is crucial for mapping peripheral devices to specific memory addresses, starting with the schematics.
- The HD6303 CPU's address space and external address bus are explained, detailing how multiple memory devices are connected.
- Ghidra disassembler is used for reverse-engineering, with steps to set up the memory map and begin disassembling the firmware.
- Understanding the reset function, interrupts, and the LCD interface provides insight into the firmware's operation.
- The article concludes with suggestions for further exploration, including the MIDI handling routine and debugging in an emulator.
- Appendices provide additional resources and documentation, including schematics, datasheets, and manuals.