Did the original ZX80 "new" ROM really contain.....

General Chit Chat about Sinclair Computers and their Clones
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Moggy
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Did the original ZX80 "new" ROM really contain.....

Post by Moggy » Sun May 26, 2019 4:08 pm

Like the majority here I do know that the original ZX81 ROM was supposed to contain some commands that were sacrificed for the printer routines. Whilst browsing through the book, "Making the most of your ZX80", I noticed the author mentions the "new" ROM available for the ZX80 and lists the commands contained therein.

For example...

DRAW
UN-DRAW
READ
DATA
RESTORE
NEW-N (n being an address to set a new ramtop value)
PRINT TO-de(used to set number output to E-notation)

Having read this I wondered is it possible that these early replacement ZX80 upgrade ROMS (as opposed to proper ZX81 ROMS) actually contained these commands or was it just a piece of the usual Sinclair sales blurb that the books author fell for?

If so it seems a shame that a half dozen or so useful commands had to give way to the routines used to power the dreadful piece of junk that was the Sinclair printer. I think a ROM with those original features would be very interesting to play with,now there's a challenge for the gurus! :lol:

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siggi
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Re: Did the original ZX80 "new" ROM really contain.....

Post by siggi » Tue May 28, 2019 9:38 am

As fa as I remember I read somewhere (in this forum???) something about the developer of this rom: he told, that the printer code was added in the final development phase just before releasing the ZX80. So maybe some prototype roms contains this code, but not the released roms.

Siggi
My ZX81 web-server: online since 2007
http://zx81-siggi.endoftheinternet.org/index.html

Bean
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Re: Did the original ZX80 "new" ROM really contain.....

Post by Bean » Thu Jun 13, 2019 4:02 pm

Somewhere I saw a picture of the prototype keyboard and it did have those keywords.
The story I heard was when the printer was developed those commands had to be removed since the ZX81 pretty much has to do all of the printer control.
This is a shame, as those commands would have been really nice to have.

Not to second guess good 'ol Clive, but I also wish the ZX81 had 4K of RAM and not have to deal with a collapsed display file. I think that would have freed up more code space to at least have the DRAW command.

Bean

Moggy
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Re: Did the original ZX80 "new" ROM really contain.....

Post by Moggy » Fri Jun 14, 2019 3:14 pm

The keywords on the prototype zx81 keyboard mentioned can be found on the slide-show featured on the Dickinson Associates site here....

http://www.theproductdesigners.com/ZX80/zx80.html
READ and RESTORE for example was on the Q/W keys. Just scroll through the ZX80 stuff to find relevant picture.

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