Currently playing about with my ZX80.
What's the best way to program it to draw a circle?
Might sound very basic but that's where i'm at!
Circles on a ZX80
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Circles on a ZX80
ZX80 (white psu)
CHROMA 80
Issue 1 ZX81
32k comp mod ZX81 filesixty keyboard
Zon X-81
Issue 1 Spectrum
Issue 2 Specrum
Toastrack
Issue 3 in Lo-Profile keyboard
Harlequin 128 in Lo-Profile keyboard
DivMMC future
vdrive
TZXduino
ZX printer
Alphacom printer
CHROMA 80
Issue 1 ZX81
32k comp mod ZX81 filesixty keyboard
Zon X-81
Issue 1 Spectrum
Issue 2 Specrum
Toastrack
Issue 3 in Lo-Profile keyboard
Harlequin 128 in Lo-Profile keyboard
DivMMC future
vdrive
TZXduino
ZX printer
Alphacom printer
Re: Circles on a ZX80
Try this and let us know how it goes:
10 FOR ANGLE = 0 TO 360 STEP 5
20 LET X = RND * 10 * SIN(ANGLE)
30 LET Y = RND * 10 * COS(ANGLE)
40 PLOT 96 + INT(X), 48 + INT(Y)
50 NEXT ANGLE
10 FOR ANGLE = 0 TO 360 STEP 5
20 LET X = RND * 10 * SIN(ANGLE)
30 LET Y = RND * 10 * COS(ANGLE)
40 PLOT 96 + INT(X), 48 + INT(Y)
50 NEXT ANGLE
Re: Circles on a ZX80
I doubt it can work.
ZX80 only uses integer math, no trigonometry, no PLOT.
Hence the question and why there was no answer.
It's far from easy if you want to calculate it.
Of course you can take a circle , convert the content to ZX80 string and print it.
But that's a solution to a different question
Or change the ZX80 ROM to a ZX81 ROM
ZX80 only uses integer math, no trigonometry, no PLOT.
Hence the question and why there was no answer.
It's far from easy if you want to calculate it.
Of course you can take a circle , convert the content to ZX80 string and print it.
But that's a solution to a different question
Or change the ZX80 ROM to a ZX81 ROM
In theory, there is no difference between theory and practice. But, in practice, there is.
Re: Circles on a ZX80
The above works with the ZX81 only. My mistake: the ZX80 only supports integers, and to create a circle, you must work with decimal numbers.
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Re: Circles on a ZX80
Yes, the lack of trigonometry functions and floating point numbers makes it a tad more difficult compared to the ZX81 ROM…
Mark
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Amp
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ZX81 Chip Pin-outs
ZX81 Video Transistor 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 being good this year.