6502 50th birthday : Habemus Spirit !

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kris92's picture
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6502 50th birthday : Habemus Spirit !

The timing is perfect for the 6502 jubilee. I'm doing the final evols to the whole design (case adjustment, hardware and firmware).At the time I'm writing, the specs are :

  •  //c case form factor
  •  WDC 65C02
  •  128K RAM
  •  32K ROM (//e ROM (no mods) + SSC)
  •  Onboard A2DVI with Apple //c keyboard switches integration
  •  Disk ][ controller
  •  4 slots (with 2 horizontal risers for 2 boards)
  •  No Slot Clock (DS1315)
  •  Super Serial Pro (FT245 chip with USB-C connectivity)
  •  Tape input port
  •  Joystick
  •  5V USB out for small external display

 

Still to be tested on current board release :

  • On board amplifier for mockingboard. Waiting for a potentiometer from eBay since almost one month :-(

To be tested on next board release :

  • Onboard Fujinet !
  • Some mecanical ajustments : Some components under the floppy were too tall : PGA 2040 will be replaced with QFN-56 chip and TH EPM7128 support will be replaced with SMD one. 3 oscillators format will be supported. Disk ][ controller chips will be directly soldered.

 

I cannot call it Apple II (I'm pretty sure to receive a mail from Apple lawyers if I even think to do so). A lot of names were possible :

  • Apple //x or //cx (for extended since this is almost a all in one Apple II)
  • Apple //p (p stand for Plamen since a lot of a2heaven boards are just fitting inside the //c case)
  • Apple //h (for hybrid)
  • Apple //a (for alternative)
  • Apple //f (for full & fast)
  • Apple //j (for jubilee, but Apple ][j already exists)

For now I choosed to name it 'Spirit ]/' since I wanted a tradeoff between the multiple Apple II designs and modern components. So the result is a motherboard with the Spirit of the Apple II. The initials specs were :

  • Use as many real components as possible. I just didn't want to build a full CPLD or software emulation.
  • Do not use MMU/IOU/KBD chips since they are no more sourcable.
  • Floppy support
  • Slots
  • Pico ATX Power Supply
  • WAF compatible form factor with modern display support. //c is great for that.

 

Two chips are no more sell : EPM7128 (cpld GLU) and 74LS323 (Disk ][ controller). But they can be easily found on eBay.

 

As I wrote in another post some months ago, my goal was not to be fully compatible with the Apple II. Unfortunately ;-), my first tests are showing a fairly very good compatibility :

  • ADTPro over USB
  • Floppy creation through Cassette input with Apple ][ Disk Server
  • A2Heaven FASTChip is almost 100% working. I discussed about a DMA problem with Plamen and found a vicious bug on 65C02 bus management (BE pin).
  • A2Heaven MegaAudio
  • Disk ][
  • A2Pico
  • XDrive
  • Prodos ROM drive
  • SP ][ SD
  • SoftSP card 
  • Total Replay : Drol, Airheart, Lode Runner, ...
  • Pascal UCSD
  • AppleWorks 2.0
  • Prodos 2.4.3
  • No Slot Clock support with Prodos
  • Joystick
  • Internal Speaker
  • ...

 

Next PCB release

I will test more A2heaven boards with my next PCB release (RAMFactor & Liron). And Z80/CPM compatibility with A2Pico.

I do not plan/want to sell boards. All files will be freely available as soon as a first design will be finalized with a minimal documentation.

Khaibitgfx's picture
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Joined: Jun 29 2019 - 20:02
Posts: 230
Congratulations

Great work!

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