vLA81 - Sinclair ZX81 ULA Replacement - NEW

As they simply don't make ZX81 ULAs anymore, then unfortunately if the ULA has failed (and there's not much else on a ZX81 to fail), then options for repair are rapidly diminishing. The vLA81 provides a simple way to keep these icons of 80's computing going.

Apart from providing the functionality of both the earlier 2C158E/184 ULA (without back porch) and the 2C210E (with back porch), the vLA81 also has a few extras added.

vLA81 features:

• Fits within the same 40 pin DIL socket outline as the original ULA.
• Narrow IC pins for easy plugin ULA replacement. In most cases the existing socket will be OK (unless, of course, the existing ULA is soldered in).
• Provides the same functionality as the 2C210E Sinclair ULA.
• Video level selectable between standard video (suitable for direct connection to a 75 ohm monitor input) and high sync level (suitable for the modulator input or some video mod boards).
• Back porch on/off select.
• Internal 32K memory support (High or Low for the different hires schemes).
• Programmable user configuration gives access to:
• Inverse or normal video and choice of black or white border.
• 50/60 Hz video standard.
• Ability to map ram to the ROM space (write protect enable/disable – 32K internal ram required).
• Tested with an extensive suite of ZX81 software.
• Ideal for preserving the original ZX81 ULA.
• Low power consumption.