Re: A86: Loading Strings and Graphics

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Re: A86: Loading Strings and Graphics


They are NOT the same processor.  The GB CPU is not even made by Zilog.  For
those of you too lazy to look it up, here is an excerpt from the pan doc.
Maybe this will inspire a few of you hunt stuff down. (hint:
http://www.devrs.com/)

Game Boy Specs
--------------

 CPU: 8-bit (Similar to the Z80 processor.)
 Main RAM: 8K Byte
 Video RAM: 8K Byte
 Screen Size 2.6"
 Resolution: 160x144 (20x18 tiles)
 Max # of sprites: 40
 Max # sprites/line: 10
 Max sprite size: 8x16
 Min sprite size: 8x8
 Clock Speed: 4.194304 MHz (4.295454 SGB, 4.194/8.388MHz GBC)
 Horiz Sync: 9198 KHz (9420 KHz for SGB)
 Vert Sync: 59.73 Hz (61.17 Hz for SGB)
 Sound: 4 channels with stereo sound
 Power: DC6V 0.7W (DC3V 0.7W for GB Pocket)


Processor
---------

  The GameBoy uses a computer chip similar to an Intel 8080.
 It contains all of the instructions of an 8080 except there
 are no exchange instructions. In many ways the processor is
 more similar to the Zilog Z80 processor. Compared to the
 Z80, some instructions have been added and some have been
 taken away.

 The following are added instructions:

  ADD  SP,nn             ;nn = signed byte
  LDI  (HL),A            ;Write A to (HL) and increment HL
  LDD  (HL),A            ;Write A to (HL) and decrement HL
  LDI  A,(HL)            ;Write (HL) to A and increment HL
  LDD  A,(HL)            ;Write (HL) to A and decrement HL
  LD  A,($FF00+nn)
  LD  A,($FF00+C)
  LD  ($FF00+nn),A
  LD  ($FF00+C),A
  LD  (nnnn),SP
  LD  HL,SP+nn           ;nn = signed byte
  STOP                   ;Stop processor & screen until button press
  SWAP r                 ;Swap high & low nibbles of r

 The following instructions have been removed:

  Any command that uses the IX or IY registers.
  All IN/OUT instructions.
  All exchange instructions.
  All commands prefixed by ED (except remapped RETI).
  All conditional jumps/calls/rets on parity/overflow and sign flag.

 The following instructions have different opcodes:

  LD  A,[nnnn]
  LD  [nnnn],A
  RETI

>
> I don't think the 86 would accept a gameboys screen, especially a gbc
> screen...
>
> >
> > It´s an interesting idea. If you can connect the screen of the GameBoy
> > to Ti86..... They have the same proccesor. They are the same thing, but
> > whith other number of keys.  :-).
> >
> > Cassady Roop wrote:
> >
> > > I think Red and Blue colors would be better for his game.
> > >
> > > Víctor Manuel Ropero Martín wrote:
> > > >
> > > > Do you want people and monsters in black and white colors?
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