Possible bug in ZX81x2 ROM ?

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1024MAK
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Re: Possible bug in ZX81x2 ROM ?

Post by 1024MAK » Fri Nov 02, 2018 10:30 pm

Every time I go to get ready to try this new ROM, someone posts another post to this thread. Which now I find I have to check in case there is a new ROM version... So I find myself in a perceptual circle... :ugeek:

Mark

PS I will try the latest version next week.

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siggi
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Re: Possible bug in ZX81x2 ROM ?

Post by siggi » Sat Nov 03, 2018 8:28 am

siggi wrote:
Fri Nov 02, 2018 9:39 pm

But I found a slightly different behavior on ZxMore: when running HRDEMO30.P: the program does not crash. But while the blinking eye is moving from left top corner to right lower corner, the screen is inverted on EO, but white on ZxMore. Also in the end some inverted screens are not inverted.
Hmm, when running the ZxMore rom (zx81x2m) on EO, the behavior is correct. So maybe it's an issue of my ZxMore (having the latest CPLD and firmware 2.0B)? Can anyone also having a ZxMore check this?

Siggi


EO_640x428.jpg
ZxMore.JPG
Last edited by siggi on Sat Nov 03, 2018 4:32 pm, edited 1 time in total.
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siggi
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Re: Possible bug in ZX81x2 ROM ?

Post by siggi » Sat Nov 03, 2018 9:43 am

@Greg: As far as I remember once Wilf wrote something, that fast screen inversion is done inside the HIRES-display routine, not by inverting the bits inside the hires picture. Maybe that is the reason, why ZxMore does not show an inverted screen as expected????

Siggi

Edit: When running a standard ZX81 rom on ZxMore, the screen also is not inverted. So it's ZxMore, not ZX81x2m, which causes this ...
Last edited by siggi on Sat Nov 03, 2018 10:10 am, edited 1 time in total.
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olofsen
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Re: Possible bug in ZX81x2 ROM ?

Post by olofsen » Sat Nov 03, 2018 9:58 am

On my ZXmore with ZXmaster 1.7 (but both when switched on and off), and an early CPLD, I do get the inverted screen. Without line 400, it is not inverted. The RAND indeed modifies the dummy display file according to the manual on page 12.

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Re: Possible bug in ZX81x2 ROM ?

Post by dr beep » Sat Nov 03, 2018 11:08 am

siggi wrote:
Sat Nov 03, 2018 9:43 am
@Greg: As far as I remember once Wilf wrote something, that fast screen inversion is done inside the HIRES-display routine, not by inverting the bits inside the hires picture. Maybe that is the reason, why ZxMore does not show an inverted screen as expected????

Siggi

Edit: When running a standard ZX81 rom on ZxMore, the screen also is not inverted. So it's ZxMore, not ZX81x2m, which causes this ...
You can indeed invert the display by setting bit 7 in the linebufferdisplay for each byte to show.
However, if you load the same code in 2 devices the display should remain the same.

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Re: Possible bug in ZX81x2 ROM ?

Post by zsolt » Thu Nov 08, 2018 5:12 pm

Moggy wrote:
Fri Nov 02, 2018 8:58 pm
Slow down Zsolt I'm running out of EPROMS!! :lol:
Sorry Moggy, here is a newer one. :lol:
Zsolt
ZX81 (8K), ENTERPRISE 128, [ZX SPECTRUM (48K,+,+128K,+2,+2A), TS1000, TS1500, TS2068, Cambridge Z88, PRIMO A64 (red)]

Moggy
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Re: Possible bug in ZX81x2 ROM ?

Post by Moggy » Thu Nov 08, 2018 6:45 pm

zsolt wrote:
Thu Nov 08, 2018 5:12 pm
Moggy wrote:
Fri Nov 02, 2018 8:58 pm
Slow down Zsolt I'm running out of EPROMS!! :lol:
Sorry Moggy, here is a newer one. :lol:
Zsolt
Thanks for this Zsolt.

I have a few maths routines which I will test this with. One example being the Collatz conjecture ,which the new ROM speeds up significantly and although in places it resorts to e-notation it retains accuracy nevertheless.

I shall program an EPROM tomorrow and see how it performs. :D


Regards.

Moggy.

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