Atari 2600: 128K/256K/512K/1MB Hozer Mega Board with working Test Software

[Atari Charles]

1 MB Mega Board with working Test Software for the Atari 2600:

 

https://www.facebook.com/GrayGamesAtari/posts/676821305763148

Edited June 11, 2015 by Atari Charles

[Atari Charles]

This Mega Board works with the following size of programs:

64K

128K

256K

512K

1MB

[Atari Charles]

The 1MB Test Program works on this.

 

 

[+SpiceWare]

Slick. What bankswitch method does it use?

[Atari Charles]

The Hozer Mega Board uses: F0

 

Randy stated, "...[W]hen you get up in the nosebleed seats it's SuperBank (SB), that's where it does simple straight addressing.

The board itself is capable of most of these or variants of them, or even mix/match. In particular the F0 would be easy to do. There's no RAM on board though, so you couldn't do CV or FA. The board I made up can use SB, and it can use F0, etc. It can use almost anything."

 

F0 (Megaboy 64K)

F0 (Hozer Mega Board 128K)

F0 (Hozer Mega Board 256K)

F0 (Hozer Mega Board 512K)

F0 (Hozer Mega Board 1MB)

 

There are more specifics, but too long and detailed to post here. Randy can probably explain it way better than I could as he makes these boards.

Edited June 12, 2015 by Atari Charles

[+SpiceWare]

Hmm, per Stella's source F0 works like this:

/**
  Cartridge class used for Dynacom Megaboy
  There are 16 4K banks.
  Accessing $1FF0 switches to next bank.

  @author  Eckhard Stolberg
  @version $Id: CartF0.hxx 3131 2015-01-01 03:49:32Z stephena $
*/

---

I think being able to only switch to bank N+1 when you're in bank N would be difficult to work with - it'd take 255 writes to $1FF0 if you needed to get to the prior bank, a minimum of 4*255=1020 cycles of CPU time. SB sounds better:

/**
  Cartridge class used for SB "SUPERbanking" 128k-256k bankswitched games.
  There are either 32 or 64 4K banks, accessible at hotspots $800 - $81F
  (32 banks) and $800 - $83F (64 banks).  All mirrors up to $FFF are
  also used ($900, $A00, ...).

  @author  Fred X. Quimby
*/

---

[Atari Charles]

The board is capable of lots of storage, but it would be up to the programmer to program. Greg had to program blind until this made was made and his code could therefore be tested. Yes it is SuperBank but that is really oversimplifying it.

[Atari Charles]

If you want more updates, go here:

https://www.facebook.com/GrayGamesAtari

[Atari Charles]

Hmm, per Stella's source F0 works like this:

/**
  Cartridge class used for Dynacom Megaboy
  There are 16 4K banks.
  Accessing $1FF0 switches to next bank.

  @author  Eckhard Stolberg
  @version $Id: CartF0.hxx 3131 2015-01-01 03:49:32Z stephena $
*/

---

I think being able to only switch to bank N+1 when you're in bank N would be difficult to work with - it'd take 255 writes to $1FF0 if you needed to get to the prior bank, a minimum of 4*255=1020 cycles of CPU time. SB sounds better:

/**
  Cartridge class used for SB "SUPERbanking" 128k-256k bankswitched games.
  There are either 32 or 64 4K banks, accessible at hotspots $800 - $81F
  (32 banks) and $800 - $83F (64 banks).  All mirrors up to $FFF are
  also used ($900, $A00, ...).

  @author  Fred X. Quimby
*/

---

 

 

Yes, Superbanking [sB] seems to be much better for larger program sizes. If you write a game lets say 32k up to 1MB, it doesn't require a rewrite of the bankswitching, just expand and keep going. You could use SB to write an 8K game if you wanted to. Someone is writing a 256K game for the Atari 2600 which will be utilizing this board. Greg and I are slowwwly working on a 1MB Atari 2600 game that will use this board. Also this board will handle BF Bankswitching as well. I have heard, not sure if it is true, that the current version of Batari Basic forces a person to be locked into BF Bankswitching if the files size is 256k or above.