Proto65 Rev0.3, A Standalone 6502 SBC Prototype

This is the link to Proto65 rev0.2, the previous iteration with display and keyboard interfaces.

This is fourth iterations of prototype 6502 computer based on Protor5. The earlier versions are built on the existing prototype area but the added video and keyboard circuits are too large to fit the existing prototype area, so the prototype area is extended with another board.

This iteration achieved the goal of Proto65 which is to develop a standalone 6502 system. A text-based monochrome VGA and a PS2 keyboard interface is added to Proto65 rev0.2.

Discussion about Proto65 rev0.3 can be found here.

• Based on protor5
  • EPM7192SQC160 CPLD
  • Reset supervisor
  • CPLD programming header
  • Reset supervisor
  • 2.1mm X 5.5mm power jack
  • Oscillator socket for full and 1/2 size can
  • Serial port interface
  • Prototype area
• 6502 CPU
• 128K 25-ns RAM based on CY7C109-25
• IDE44 interface for CF disk
• I2C Bus
• VGA and keyboard daughterboard
  • 64 columns, 48 rows text-based monochrome VGA
  • 4K dual-port RAM for video data and character fonts
  • PS2 keyboard interface

Schematic

CPLD design