Classic Intel 8080 Microprocessor Emulated on Contemporary FPGA
In a captivating display of retro computing enthusiasm, [Mark] has unveiled an impressive Intel 8080 build, showcasing the vendor-free, open-source revival of a nearly 50-year-old CPU. Using a modern Microchip FPGA, [Mark] has constructed a comprehensive system board for the 8080A-1, pushing the CPU to run competently at 3.125 MHz. Notably, every aspect of this project is open source, eschewing proprietary flashing tools and vendor lock-in.
Bringing this vintage setup to life demanded more than mere logic. To facilitate the 8080's operation, [Mark]'s board offers both the essential ±5 V and +12 V rails, along with clock and memory interfacing through the M2GL005-TQG144I FPGA. The design is streamlined, featuring a two-layer PCB, fundamental level-shifters, and a CM32 micro as a backup USB-to-UART interface. Despite encountering tribulations—such as incorrect footprints, misrouted gate drivers, and thermal runaway in the clock section—[Mark] successfully overcame these challenges.
What sets this project apart is the nostalgic resurrection of the venerable 8080 CPU. Moreover, the thoughtful modern integration of the FPGA—from bitstream loading via OpenOCD to the creative debugging of crystal oscillator drift using a scope—is a testament to [Mark]'s admiration for the architecture and meticulous approach to low-level details. In essence, this transcends being merely a showcase project.
- Mark has adapted an open-source FPGA to his PCB for the 8080A-1, allowing gadget enthusiasts to tinker with data-and-cloud-computing technologies using the revived Intel 8080.
- This nostalgic 8080 CPU project, featuring a comprehensive two-layer PCB and CM32 micro for backup, showcases Mark's FPGA enhancement, exemplified by open-source bitstream loading via OpenOSCD and innovative crystal oscillator debugging.
- With the open-source integration of a modern FPGA onto a PCB for the Intel 8080, Mark's work brings together vintage computing and state-of-the-art technology, allowing hobbyists to delve into the intricacies of the 8080 design with ease.
