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SBC1802 #Homebrew

Timothy Stoddard
 
Edited

I have been an inactive member for quite a while... this is my first post and is of my SBC1802 build using heat vaporized wiring pencil. I posted a some pictures in the Photos area.
Here are the specs:

 

  • CDP1802CE
  • All status signals displayed
  • Mode and state codes decoded and displayed
  • slow (555), 1.79MHZ, and external clock
  • TIL311 displays
  • full address display
  • data display selectable for ports 1-7
  • HEX keypad input (74C923) via DMA or any port 1-7 (matches the display port)
  • 32KB SRAM (lower bank)
  • 32KB EEPROM (upper bank) with write protection
  • dual buck regulators (one for the displays and related circuitry, one for the CPU and related)
Looking to add a CDP1854 on the 'standard' ports and run figForth on this!
 

David Schultz
 

On 2/27/19 7:55 AM, @Timothy wrote:
Looking to add a CDP1854 on the 'standard' ports and run figForth on this!
 
Keep in mind that figForth is expecting the RCA multi level I/O system
which multiplexes different hardware between the I/O ports and also the
EF inputs. If you don't have a lot of I/O it is safe to ignore it.

Or you can modify the I/O in figForth.

The RCA Microboards catalog has a 18S605 schematic with the details.


--
http://home.earthlink.net/~david.schultz
The cheaper the crook, the gaudier the patter. - Sam Spade