ZXmore - questions and answers (FAQ)

Any discussions related to the creation of new hardware or software for the ZX80 or ZX81
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rune
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Re: ZXmore - questions and answers (FAQ)

Post by rune » Mon Aug 21, 2017 1:45 pm

Hi, Im getting the parts together for my ZX More. One chip I cant seem to get is a 74HCT85

Farnell dont stock them. eBay sellers want around 4.50 for one. What is the chip used for and can anyone advise where I can get one at a sensible price?

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1024MAK
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Location: Looking forward to summer in Somerset, UK...

Re: ZXmore - questions and answers (FAQ)

Post by 1024MAK » Mon Aug 21, 2017 4:29 pm

Rapid, Farnell, CPC, RS and TME / Multisort Elektronik Limited don't have any listed, true. If you ask Farnell or RS they, they may be able to get some for you.

These suppliers however do list them:
https://www.digikey.co.uk/product-detai ... 5-ND/38770

http://www.mouser.co.uk/Semiconductors/ ... 85&FS=True

At this point I stopped looking.

I'd have to check the schematic, but it's likely a 74HC85 would work. And it's also possible that a 74LS85 may work.

Mark

rune
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Re: ZXmore - questions and answers (FAQ)

Post by rune » Mon Aug 21, 2017 8:31 pm

Thanks Mark, I'll wait for the current batch of bits to arrive and then assess whats needed to complete the board.

The alternatives are useful as they are inexpensive and worth trying.

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PokeMon
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Re: ZXmore - questions and answers (FAQ)

Post by PokeMon » Wed Aug 23, 2017 12:53 pm

I use 74HC85 for that in my assembly kits. ;)

rune
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Re: ZXmore - questions and answers (FAQ)

Post by rune » Sun Aug 27, 2017 8:36 pm

Thanks for that Pokemon & Mark. I have the 74HC85 and its in the PCB. I dont have much more to do now, just power, composite, Inductor, ROM switch and the pair of 2x5 resistor networks to go. All ordered except for the last two items. I can stand resistors vertically and don't need the switch immediately.

Can you tell me...

Is the Spectrum available as an option?

Can I run the H4th Rom?

Can I use a Vdrive with any of the ROMs?

Is there any central source for ZXMore/ZXMaster documents.

I am looking forward to getting this board running.

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PokeMon
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Re: ZXmore - questions and answers (FAQ)

Post by PokeMon » Mon Aug 28, 2017 9:05 pm

Here the construction kit manual:
ZXmore-V2-ConstructionKit.pdf
(1.17 MiB) Downloaded 17 times
Here is the latest schematic for ZXmore V2
ZXmore - Project.pdf
(373.46 KiB) Downloaded 15 times
Here is the user manual (complete ZIP including software for update)
ZXmore2-V19-usermanual.pdf
(1.58 MiB) Downloaded 21 times
Spectrum is not ready yet but I am working on the CP/M first now as there was more request from users.

Vdrive should be possible to use in general with any ZX81 ROM when loaded/programmed at a proper location in the flash rom. I don't have experience with Vdrive personally but there shouldn't be any hardware conflict with default Vdrive IO address 7Fh. But you can use the usb flash drive (upper port of both) to load and store programs. With the current release there is a lack of subdirectory support but in further releases this will be possible, too.

Maybe try to get the board run in general first and read through the manual and experiment with it. ;)

rune
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Re: ZXmore - questions and answers (FAQ)

Post by rune » Mon Aug 28, 2017 9:43 pm

Thanks for the links and information.

I have the docs already, but am a confused with the version numbers

My ROM is marked as V2.1 with a date of 07/2017 and the CPLD? has a V2.19a with a date of 08/2017. I thought/hoped that this would have sub directories.

But you say that V1.9 is the latest version?

Also the V2 construction document shows 2 diodes marked in a photo at the "Step 2 Diodes" section, but these aren't on my board. Are they a modification or been dropped?

OK, no problem re the Spectrum implementation. I'll need to look into CM/P then.

Until I get the rest of the components, its :?: questions, :?: questions, :?: questions.... :P :idea:

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PokeMon
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Re: ZXmore - questions and answers (FAQ)

Post by PokeMon » Mon Aug 28, 2017 10:15 pm

Yes - there are some modifications and I am not sure that every picture matches exactly to the latest board revision.
And the mismatch between hardware revision (CPLD) and software revision is normal as the software changes faster and more often than hardware (hopefully). But in general this is. V2 marks the CPLD for the newer board which is somehow different but will operate with the same software in future as the first V1 boards.

V2-19 is the latest hardware revision (for the V2 boards) and V2.1C the latest software revision.

olofsen
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Re: ZXmore - questions and answers (FAQ)

Post by olofsen » Tue Aug 29, 2017 9:38 pm

The H4TH ROM from http://forum.tlienhard.com/phpBB3/viewtopic.php?t=2076 runs on my early ZXmore with an early CPLD. LOAD from and STORE to (simulated) USB works also with sz81 version 2.3.7 from http://rullf2.xs4all.nl/sz81/ when ZXmore support is enabled.

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PokeMon
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Re: ZXmore - questions and answers (FAQ)

Post by PokeMon » Tue Aug 29, 2017 10:25 pm

Actually I didn't remember the latest progress on this project - thanks for pointing out.
And thanks for all your work and personal effort on the H4TH. ;)

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