CPCX

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The CPCX is an add-on card for the CPC.

From the CPCWIKI forum:

The card is a prototype, but is built with simple chips and should be easy to build even with recycled items only. There are no strange part (GAL, ROM, FPGA...) and youshould only need a soldering iron and some classic electronics tools. The PCBs are double-sided and not multilayered. You will spend some time on it because there are many holes to do, however.

http://irios.free.fr/ you may or may not find irios's mail address somewhere here.

About the memory banks:

It is based on the system of the CPC, so we have 16k pages of ram. However, I don't see how overscan can be done as you can only access one "video" bank at a time... And I don't understand how the internal CRTC could access the external bank ram, too (on CPC the CRTC only access the centra ram...), so this would require an external CRTC or make the banked system only accesible to the VGA system. In the end the system will only use the z80 and keyboard from the CPC, everything else beingdone on the external card. The memory scheme used combines the ram expansion and rom expansion capabilities of the cpc to make various banks with each different commutable pages, I think this could break many CPC applications... so this board looks like a new computer build on the base of the CPC.

Sound

  • 6 channel, 8 octave (AY-3-8912 and AY-3-8910)
  • Stereo soundtrack 8 bit with 4Mo memory for each channel
  • Programmable sampling frequency
  • Discrete DAC (R/2R)
  • Programmable ticker with 3 interrupts levels
  • Automatic ram refresh

Video

  • 16kB standard CPC, 8MB for 256 video pages
  • 1MB VGA

Ram

  • 128kB CPC, 8 MB

Rom

  • 512kB SRAM used as ROM

I/O

  • Serial port
  • 4 floppy drives
  • 2x 3"/360k
  • 2x 3"5/ 1.44MB or 720k
  • Tape
  • Cdrom
  • IDE hard drive
  • Parallel port

Other

  • 3 timers
  • Z80 @ 10MHz