ZXmore - infos & updates

Any discussions related to the creation of new hardware or software for the ZX80 or ZX81
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1024MAK
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Re: ZXmore - infos & updates

Post by 1024MAK » Fri Jul 21, 2017 3:06 am

Not to rain too much on your parade, but I have a bit of, okay a large OCD thing about video standards.
PAL is only a colour encoding system, NOT a video or TV standard. PAL can encode colour for 525 line, 15750 Hz horizontal, 60 Hz vertical (field) / 30 Hz frame TV video signals (as used in Brazil). So PAL does not always mean a 625 line 50Hz video signal.

Conversely, it is possible to encode colour for a 625 line 50Hz video signal using NTSC. In France, they did not use PAL or NTSC, instead they used SECAM to encode the colour part of the video signal. And yes, NTSC 625 line 50Hz video has been tested and found to work okay.

In Germany and the UK, ZX80, ZX81, ZX Spectrum's, and of course, the two computers developed by Karl all generate 625 line, 15625 Hz horizontal, 50 Hz vertical (field) video signals (in the UK, this is known as the ITU standard system I). As ZX80, ZX81 and Karl's designs don't produce colour video, they don't have a colour encoder system. So PAL/NTSC does not apply. The ZX Spectrum does use a colour encoder, so does produce a PAL colour signal.

So to sum up:
USA colour analogue TV used the ITU NTSC-M standard.
UK colour analogue TV used the ITU PAL-I standard.
French colour analogue TV used the ITU SECAM-L standard.
In the USA, TS1000 computers use the ITU M standard.
In the UK, ZX81 computers use the ITU I standard.

Broadcast television systems and Analog television - Standards

Mark

tdg8934
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Re: ZXmore - infos & updates

Post by tdg8934 » Fri Jul 21, 2017 3:25 am

Thanks Marc for the education. Good to know.

Karl or anyone,
I have been able to get most normal zx81 P programs to load ok (I think). However, the HR ones don't and I may just not be familiar with the formats and if they need to be loaded into an upper part of memory. Can anyone point me to some ZXmore working HR programs/games so I can see what works. From what I have seen so far after a double shift L for a USB load, some programs cause the monitor to go blank (black) and some cause the cassette tape display screen to come on and others do nothing. I would like to make sure ZXmore can run all Hires programs and let me know specifically what I need to do.

Thanks - Tim

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PokeMon
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Re: ZXmore - infos & updates

Post by PokeMon » Thu Aug 03, 2017 2:31 pm

tdg8934 wrote:
Fri Jul 21, 2017 12:34 am
Karl - is there any switch or solder point on the ZXmore to have the output on the ZXmore in NTSC video and not PAL? If not it's ok but it's ok since my new composite video to HDMI converter accepts PAL and converts it to HDMI for the monitor. However, it would be nice to have it in NTSC so I can prove my cheaper composite video to VGA works also.
Yes, there is a jumper to select near C34 in the picture above. If jumper set, it is NTSC selected and if not set (default) it is PAL as we use on this side of planet mostly. ;)

By the way, you could try
http://www.swatosch.de/zx81/
for HRG programs (running in my environments) or the classic hr 1 k demo from Wilf Rigter, There are some HRG applications or programs not running with the ZXmore but in the meantime running with ZXblast - so hopefully can be solved. Mostly are just demos. You can also try to load such demos with ! character at the end of the file name during loading routine.

brunosilva
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Re: ZXmore - infos & updates

Post by brunosilva » Sun Nov 25, 2018 1:11 pm

zxmore is still available to buy?

brozier
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Re: ZXmore - infos & updates

Post by brozier » Mon Nov 26, 2018 10:07 am

brunosilva wrote:
Sun Nov 25, 2018 1:11 pm
zxmore is still available to buy?
Looks like Karl is on holiday until after Christmas :-

https://www.sellmyretro.com/offer/details/32842

tdg8934
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Re: ZXmore - infos & updates

Post by tdg8934 » Fri Oct 04, 2019 3:24 pm

Karl,

My V2-19 ZXMore has stop working on instance rom switch 0 for the menu. I saw it briefly come up the other day but when I switch to other instances and back to 0 it’s blank. I tried unmodifying it for use with ZxPand (removed connection of 10k resistor between A7 top pin and 5vdc and removed the top jumper on A3 top and bottom pins). It still only has the instances 1-7 and higher but nothing on instance 0. No menu to load/save usb and other features. If I put the ZxPand modifications back and I get a blank instance 0 screen but the other instances seem to be the same meaning if on instance 1 I write a program , I see the program on the other instances 2-7 and greater.

Ideas to try?

Thank you. (Tim)

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1024MAK
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Re: ZXmore - infos & updates

Post by 1024MAK » Fri Oct 04, 2019 5:23 pm

tdg8934 wrote:
Fri Oct 04, 2019 3:24 pm
Karl
Tim

Karl / PokeMon is not very active on this board this year. I suggest you PM him, or if you have an email address for him, contact him by email.

Mark

tdg8934
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Re: ZXmore - infos & updates

Post by tdg8934 » Fri Oct 04, 2019 5:33 pm

Thanks Mark.

olofsen
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Re: ZXmore - infos & updates

Post by olofsen » Fri Oct 04, 2019 11:10 pm

Tim, do you still have a jumper at J12 to set the i/o address to the one the ZXmaster is expecting?

tdg8934
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Re: ZXmore - infos & updates

Post by tdg8934 » Fri Oct 04, 2019 11:50 pm

With the modification made for the ZXPand/ZXPand+ (10k resistor on j12 A7 to +5vdc and removed jumper from A3) if gives me the same instance on all rom switch 1-7. But rom switch 0 is blank. If I connect A3 with a jumper (or other ones) then rom switch instance 0 shows a graphic scramble. I’ve showed this in the past.

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