Taken from a PDF I've been reading
Saving Memory on the Sinclair ZX81Sean A. Irvine Hamilton, New Zealand.
"Another oddity is that an isolated period (.) is a valid representation for 0 on the ZX81.Therefore, it was
possible to go through a program after it was written and compress out all but one of the visible digits in a number (and the last remaining digit could be replaced with . if desired)."
Is this possible and does it have any real world use programming wise?
PDF found here..
https://www.zx81.nl/dload/zx81-memory.pdf
Replacing numbers with a full stop.
- 1024MAK
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Re: Replacing numbers with a full stop.
Mark
ZX81 Variations
ZX81 Chip Pin-outs
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ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
Re: Replacing numbers with a full stop.
Ha I see so when declaring variables for example such as,LET A=0,LET B=0 etc the six byte overhead that using a zero causes can be saved by using the full stop instead.
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: Replacing numbers with a full stop.
Don’t know, I just wanted to try it and see if the syntax checker would allow it!
Mark
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
Re: Replacing numbers with a full stop.
No memory saved using a dot…
Use " LET A=PI-PI"...
Use " LET A=PI-PI"...
Xavier ...on the Facebook groupe : "Zx81 France"(fr)
Re: Replacing numbers with a full stop.
Try
LET A = NOT PI
LET A = NOT PI
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