Anyone know useful ZX80 ROM tricks?

Anything Sinclair ZX Basic related; history, development, tips - differences between BASIC on the ZX80 and ZX81
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PokeMon
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Re: Anyone know useful ZX80 ROM tricks?

Post by PokeMon » Fri Mar 31, 2017 2:43 pm

Shaun_B wrote:
Fri Mar 31, 2017 12:06 pm
I signed up to the German forums, I hope that I get approved.
Just simply ask your questions in english and we know better what you want and you don't have to translate the answers.
Translation can be horrible sometimes. Whoever read a translated chinese manual or description, knows what I mean. :lol:
As we speak German does not mean we don't understand english or want avoid english stuff on that forum. ;)

Shaun_B
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Re: Anyone know useful ZX80 ROM tricks?

Post by Shaun_B » Tue Apr 04, 2017 12:19 pm

Here is a listing that will allow you to handle floating point numbers between 0.00 and 327.67 on the original ROM-sporting machines:

Code: Select all

10 INPUT M
20 LET M=ABS(M)
30 LET S$="."
40 PRINT M/100;S$;
50 LET R$=STR$(M)
60 IF M<10 THEN PRINT "0";
70 IF M>99 THEN LET R$=TL$(R$)
80 IF M>999 THEN LET R$=TL$(R$)
90 IF M>9999 THEN LET R$=TL$(R$)
100 PRINT R$

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PokeMon
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Re: Anyone know useful ZX80 ROM tricks?

Post by PokeMon » Tue Apr 04, 2017 12:31 pm

This can be done shorter, I think:

Code: Select all

10 INPUT M
20 LET M=ABS(M)
30 LET F=M/100
40 LET R=M-F*100
50 PRINT F;".";
60 IF R<10 THEN PRINT "0";
70 PRINT R

Shaun_B
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Re: Anyone know useful ZX80 ROM tricks?

Post by Shaun_B » Tue Apr 04, 2017 4:24 pm

Good tip.

dr beep
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Re: Anyone know useful ZX80 ROM tricks?

Post by dr beep » Tue Apr 04, 2017 4:54 pm

It makes me search the ROM and thinking of hires on 1K ZX80.....

Shaun_B
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Re: Anyone know useful ZX80 ROM tricks?

Post by Shaun_B » Tue Apr 04, 2017 5:54 pm

Is high resolution even possible on a ZX80?

Regards,

Shaun.

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PokeMon
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Re: Anyone know useful ZX80 ROM tricks?

Post by PokeMon » Tue Apr 04, 2017 5:55 pm

Yes, depends on screen resolution and memory. The hardware is the same (except missing NMI generator).

dr beep
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Re: Anyone know useful ZX80 ROM tricks?

Post by dr beep » Tue Apr 04, 2017 6:02 pm

Therefore a different start is needed, checking ROM now....

Shaun_B
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Re: Anyone know useful ZX80 ROM tricks?

Post by Shaun_B » Tue Apr 04, 2017 6:04 pm

Dr Beep, please share your findings :)

Regards,

Shaun.

dr beep
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Re: Anyone know useful ZX80 ROM tricks?

Post by dr beep » Tue Apr 04, 2017 6:34 pm

How do I load a game in EightyOne in ZX80 mode?
I only get a full black screen with a game I found.

Edit: got something....

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