Designing a 5x8 matrix allows the system to read 40 keys without needing a dedicated keyboard controller IC. 3. Retro Computer Design: Recreating the ULA Today
The Z80 needs a defined map where the ROM resides at $0000 and RAM follows. The ULA must ensure that the video circuitry has access to the RAM to draw the screen, causing the CPU to "wait" periodically (contention).
While not pure hardware emulation, high-speed microcontrollers can run software emulators fast enough to simulate the ULA and Z80, outputting video directly to an LCD. 2. Video Processing for Portable Screens Designing a 5x8 matrix allows the system to
If your goal is a portable device, focus on these integration steps: Building a Pocket ZX Spectrum | PDF - Scribd
So, how does this history lesson help you build a "portable retro computer"? The ULA must ensure that the video circuitry
– Contended memory state machine:
The original ZX Spectrum was small, but modern technology allows for truly "portable" retro designs. Video Processing for Portable Screens If your goal
Use an FPGA to output clean or digital HDMI/DVI signals.
Here’s a for a retro-inspired portable microcomputer based on the ZX Spectrum ULA design philosophy:
The ZX Spectrum, released in 1982, was one of the most popular home computers of the 1980s. Its success can be attributed to its affordability, accessibility, and the creativity of its users. At the heart of the ZX Spectrum lies the Uncommitted Logic Array (ULA) chip, a custom-designed integrated circuit that played a crucial role in the machine's performance and capabilities. In this article, we'll delve into the world of retro computing and explore how to design a microcomputer using the ZX Spectrum ULA.
The philosophy of the ULA—integrating complex systems into a single chip—is exactly what powers our smartphones today. The System-on-Chip (SoC) in your pocket is the great-great-grandchild of the Ferranti ULA.