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Because I have not tested all electronic circuits mentioned on this pages, I cannot attest to their accuracy; therefore, I do not provide a warranty of any kind and cannot be held responsible in any manner.
6502 Single Board Computers
6. August 2008 - 19:45 — admin
An inexpensive 65c02 based single board computer by Daryl Rictor.
Of course, you can buy new 6502 microprocessor clone - and you can build a simple computer based on 6502 too. Check out the Daryl's pages, you find a pair of 6502-based SBCs.
This SBC (version 1.1) includes a 1Mhz 65C02, 32K RAM, 32K ROM, and a 6522 CIA, and necessary logic to make it all work together.The design is very straightforward.It is used a 1 MHz TTL Oscillator for timing and three standard 74LSXX chips for decoding.
SBC-2.3 includes space for a 1 MHz 65c02, 32K of static RAM, and 32k of EEPROM. It also has two 65C22 Versatile Interface Adapters (VIA) and one 65c51 Asynchronous Interface Adapter.
SBC-2 v2.5 is a slightly modified version of the 2.3 board. The modifications include addition of a 7805 voltage regulator, more space around the EEPROM pads to allow for a ZIF socket, reconfiguration of the Serial port Connector, and addition of all address lines to the expansion connector.
SBC-3 is Daryl's latest design. It is still in development, but here are some details:
It will have the 65816 microprocessor, running at 7.159 MHz. It can directly address the 512K of system RAM. The video system uses the transparent DMA method. During the low phase of PHI2, the CPLD accesses RAM and outputs pixel data to the video system. During the high phase of PHI2, the CPLD lets the MPU access RAM. The Video output is 320x200 pixels, using 8 bits per pixel (256 colors).