[Aquarius] can't we use Halt for waitvbl? (video blank sync)

[nitrofurano]

when using Boriel's ZX-Basic Compiler for coding stuff for ZX-Spectrum or MSX, or even coding directly in assembly on them, i use Halt (z80 operand) for waitvbl (video blank sync) - it seems that we can't do that on Aquarius, and there is no syncronization at all between z80 and the video processor, like happens on GEM-1000/MC-1000? should we use instead a kind of bc decrement delai routine for that?

[mvdsteenoven]

when using Boriel's ZX-Basic Compiler for coding stuff for ZX-Spectrum or MSX, or even coding directly in assembly on them, i use Halt (z80 operand) for waitvbl (video blank sync) - it seems that we can't do that on Aquarius, and there is no syncronization at all between z80 and the video processor, like happens on GEM-1000/MC-1000? should we use instead a kind of bc decrement delai routine for that?

 

Check out the VSYNC discussion in Aquarius machine language programming, second page

 

Martin

[nitrofurano]

Check out the VSYNC discussion in Aquarius machine language programming, second page

 

Martin

i'm struggling on finding it... :S

[catsfolly]

i'm struggling on finding it... :S

 

I think he means here:

 

http://atariage.com/...us/page__st__25

 

 

At

http://www.vdsteenov...rius/iomap.html

we can read:

 

 

The current state of the vertical sync will appear on bit 0 during a read of this port[FD]. The waveform and timing spec is shown as follows:

 

 

 

 

Does this help?

 

Looking good so far....

[nitrofurano]

so i imagine

halt

would be replaced with something like:

loopvbl:
in($FD)
and $01
jp z,loopvbl" ;(or perhaps "jp nz,loopvbl" ?)

?

Edited July 1, 2013 by nitrofurano