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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Joined: Wed Jun 18, 2008 2:00 pm

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

Post by Moggy »

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 »

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

Post by Bean »

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 »

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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