Difference between New rom and Old Rom

Anything Sinclair ZX Basic related; history, development, tips - differences between BASIC on the ZX80 and ZX81
Lardo Boffin
Posts: 1071
Joined: Sat Nov 26, 2016 2:42 am

Re: Difference between New rom and Old Rom

Post by Lardo Boffin » Fri Apr 05, 2019 8:27 am

Do you mean the ZX81 ROM with the math error?

I have sold a couple of these to people on this site - maybe they have the facility to dump them? I have a buggy ROM but no way to dump it.

Lardo
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
Iss 3 ZXVid
TS 1000 iss 3, ZXPand AY, ZX8-CCB, ZX-KDLX & ChromaSCART
TS 1500
TS 2000
Spectrum 16k (iss 1 s/n 1499)
Various Spectrum 48ks plus a DIVMMC future and SPECTRA

Moggy
Posts: 1864
Joined: Wed Jun 18, 2008 2:00 pm

Re: Difference between New rom and Old Rom

Post by Moggy » Fri Apr 05, 2019 4:59 pm

Like Lardo I too have said ROM so will have a play around tonight by fitting it to my test zeddy and dumping its contents to the ZXpand, save it and post on here as a P file if that helps?

Moggy
Posts: 1864
Joined: Wed Jun 18, 2008 2:00 pm

Re: Difference between New rom and Old Rom

Post by Moggy » Fri Apr 05, 2019 8:56 pm

As promised the old bugged ROM in P file format.

To view load into ZXspand at suitable address as per the manual (I chose 32767) or block load into Eighty One.

To turn this into something usable I leave to others as my learning doesn't stretch that far. :oops:
Attachments
OLDROM.P
(8 KiB) Downloaded 41 times

User avatar
RetroTechie
Posts: 379
Joined: Tue Nov 01, 2011 12:16 am
Location: Hengelo, NL
Contact:

Re: Difference between New rom and Old Rom

Post by RetroTechie » Sat Apr 06, 2019 11:02 am

Thanks for your trouble Moggy! :)

Works as-is as ZX81 ROM (in emulators at least). Simply rename .p -> .rom or .bin as desired.

Moggy
Posts: 1864
Joined: Wed Jun 18, 2008 2:00 pm

Re: Difference between New rom and Old Rom

Post by Moggy » Sat Apr 06, 2019 12:17 pm

No trouble RT glad to help will rename as you suggested and try it out in Eighty One. :D

EDIT.
Just realised this ROM already exits in the ROM folder of Eighty One!!!! :oops: :oops:

Crayon21
Posts: 116
Joined: Sun Nov 04, 2018 2:33 am

Re: Difference between New rom and Old Rom

Post by Crayon21 » Sun Apr 07, 2019 2:48 am

Moggy wrote:
Sat Apr 06, 2019 12:17 pm
No trouble RT glad to help will rename as you suggested and try it out in Eighty One. :D

EDIT.
Just realised this ROM already exits in the ROM folder of Eighty One!!!! :oops: :oops:
someone slipped on the proverbial banana peel :lol:
zx81: great yet flawed
Zx spectrum: masterpiece that keeps on giving

(wish it weren't so expensive) :o

User avatar
mrtinb
Posts: 1062
Joined: Fri Nov 06, 2015 5:44 pm
Location: Denmark
Contact:

Re: Difference between New rom and Old Rom

Post by mrtinb » Sun Apr 07, 2019 9:21 am

Crayon21 wrote:
Fri Apr 05, 2019 2:08 am
(sigh) is there an assembler for the zx81 already out there?
Many!
Someone also made a starting guide for cross compiling on a PC, if that's what you prefer.
Martin
ZX81, Lambda 8300, Commodore 64, Mac G4 Cube

Moggy
Posts: 1864
Joined: Wed Jun 18, 2008 2:00 pm

Re: Difference between New rom and Old Rom

Post by Moggy » Sun Apr 07, 2019 1:29 pm

If you posses a ZXpand I can supply the EPROM code for the Memotech Z80 assembler interface which when loaded in the ZXpand to the address in the memory map this interface occupies allows the ZXpand to imitate the device.

The self running P file loaded from the memory card does all that is needed for this then just follow the manual which I can also supply.

User avatar
mrtinb
Posts: 1062
Joined: Fri Nov 06, 2015 5:44 pm
Location: Denmark
Contact:

Re: Difference between New rom and Old Rom

Post by mrtinb » Sun Apr 07, 2019 2:05 pm

Moggy wrote:
Sun Apr 07, 2019 1:29 pm
If you posses a ZXpand I can supply the EPROM code for the Memotech Z80 assembler interface which when loaded in the ZXpand to the address in the memory map this interface occupies allows the ZXpand to imitate the device.

The self running P file loaded from the memory card does all that is needed for this then just follow the manual which I can also supply.
You see, that’s something I would like to try.
Martin
ZX81, Lambda 8300, Commodore 64, Mac G4 Cube

Moggy
Posts: 1864
Joined: Wed Jun 18, 2008 2:00 pm

Re: Difference between New rom and Old Rom

Post by Moggy » Sun Apr 07, 2019 8:47 pm

Here you are Martin.

In the folder are three files. ASSEMBLE.P ASMBIN.P and finally the text manual.

Making sure the two P files are in the same folder. Load the self running file ASSEMBLE.P which will then do two things.

1) It lowers ramtop down to the example shown in the manual. The two pokes in the listing for ASSEMBLE.P can be altered to what ever suits you, I used this setting only to illustrate the manuals example.

2) It will then load the ROM code (ASMBIN.P) to an address in the ZXpand identical to the one the original interface occupied(12288), the zeddy then resets leaving the code in place.

Once this is done just read the manual and away you go!!

The assembler listing is divided into three columns and to go from column one to column two/three you have to shift Z which is ok on original membrane keyboard but if using the Memotech Keyboard it sometimes leaps an extra space so you have to erase and start again which is a bit of a pain but much fun all the same.

Have fun!! :D
Attachments
z80assenbler.zip
(11 KiB) Downloaded 44 times

Post Reply