ZX81 Assembly Programming - Getting Started

Any discussions related to the creation of new hardware or software for the ZX80 or ZX81
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Zac
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Re: ZX81 Assembly Programming - Getting Started

Post by Zac »

I've just compared the same .p file on vb81 and eightyone emulators...

Eightyone is 30 time speedless than vb81... Have you already seen that ?
-=Zac
sirmorris
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Re: ZX81 Assembly Programming - Getting Started

Post by sirmorris »

I can't say I've had a problem with EO speed-wise. What are you seeing? You are requesting a one second delay in between each character..
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Paul
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Re: ZX81 Assembly Programming - Getting Started

Post by Paul »

Zac wrote:I've just compared the same .p file on vb81 and eightyone emulators...

Eightyone is 30 time speedless than vb81... Have you already seen that ?
I have not really understood this message.
Is eightyone 30 times faster than vb81 or is vb81 30 times faster than eightyone?
I guess both have the option to emulate the correct speed? EO has, I don't know about vb81. Never tried that one :oops:
In theory, there is no difference between theory and practice. But, in practice, there is.
sirmorris
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Re: ZX81 Assembly Programming - Getting Started

Post by sirmorris »

Your program should take about 11 seconds to execute. If it takes more than 330 seconds to run then there is a real problem..!
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Zac
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Re: ZX81 Assembly Programming - Getting Started

Post by Zac »

Sorry for short description ...

To have a signifiant comparaison, i made a longer string :

Code: Select all

line:		DEFB  _H,_E,_L,_L,_O,$00,_W,_O,_R,_L,_D,$_NL,
				DEFB	_W,_E,_L,_C,_O,_M,_E,__,_T,_O,__,_Y,_O,_U,$_NL
				DEFB	_A,_N,_D,__,_H,_A,_V,_E,__,_A,__,_G,_O,_O,_D,__,_D,_A,_Y,$_NL
				DEFB	$ff
on EightyOne : 75 seconds
on VB81_XuR : 5 seconds

for the same program with $0050 value for PAUSE...
-=Zac
sirmorris
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Re: ZX81 Assembly Programming - Getting Started

Post by sirmorris »

There are 48 characters. The pause is 80 frames per character, which on a PAL machine is about 1.6 seconds.

48 characters * 1.6 seconds ~= 76 seconds.

This is what I'd expect. EO is correct.

C
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Zac
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Re: ZX81 Assembly Programming - Getting Started

Post by Zac »

Thank you Sir Morris, so if i want introduce some pause in future program, i must use eight one (for tests) to be sure it will be the same result on a real ZX81 ?
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sirmorris
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Re: ZX81 Assembly Programming - Getting Started

Post by sirmorris »

Yes, it seems so. I'm sure there would be a way to make vb81 produce accurate timing though.
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PokeMon
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Re: ZX81 Assembly Programming - Getting Started

Post by PokeMon »

sirmorris wrote:There are 48 characters. The pause is 80 frames per character, which on a PAL machine is about 1.6 seconds.

48 characters * 1.6 seconds ~= 76 seconds.

This is what I'd expect. EO is correct.

C
Maybe it's more convenient to use decimal values for PAUSE.
50 is exactly one second (more or less), easier to calculate. ;)
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Zac
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Re: ZX81 Assembly Programming - Getting Started

Post by Zac »

Good idea PokeMon, Thanks ;)
-=Zac
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