HOT-Z Keys

Discussion about ZX80 / ZX81 Software
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GCHarder
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HOT-Z Keys

Post by GCHarder » Mon Jun 09, 2014 6:10 pm

Hot-Z.jpg
Hot-Z splash screen
Hot-Z.jpg (12.2 KiB) Viewed 933 times
HOT-Z is a "real time" assembler/disassembler for the ZX81 written by Ray Kingsley. All my old MC programs were produced using it, It is still a great program, unfortunately, I've not been able to find the manual for it anywhere online. Manual has since been posted by Steve McDonald, see below.

Regards;

Greg
Last edited by GCHarder on Mon Jun 05, 2017 9:31 pm, edited 1 time in total.

PeekPoke
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Re: HOT-Z Keys

Post by PeekPoke » Fri Jul 15, 2016 5:23 pm

Sorry for digging out this old thread but :oops:

Typed RAND USR 38912 (Read me file) to get it running

But always got an error message...

Thanks for your help. ;)

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GCHarder
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Re: HOT-Z Keys

Post by GCHarder » Fri Jul 15, 2016 8:13 pm

This program is one of the few which RUNs in upper memory, 8000H. As such, on a real ZX81, you have to have the hardware mod called "M1 NOT" installed otherwise M.C. programs will not run, has something to do with the video display, but not sure about that. In Eighty one emulator you can activate the M1NOT mod in the advance options menu.

I know that works, as I use it often.

Regards;

Greg

PeekPoke
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Re: HOT-Z Keys

Post by PeekPoke » Fri Jul 15, 2016 9:19 pm

Thank you very much Greg.

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1024MAK
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Re: HOT-Z Keys

Post by 1024MAK » Fri Jul 15, 2016 11:29 pm

GCHarder wrote:This program is one of the few which RUNs in upper memory, 8000H. As such, on a real ZX81, you have to have the hardware mod called "M1 NOT" installed otherwise M.C. programs will not run, has something to do with the video display, but not sure about that.
The ZX81 makes use of incomplete memory address decoding, so uses a memory echo / shadow of the RAM in an unconventional way to produce the display.

The name comes from a Z80 CPU status line called /M1 which indicates that the Z80 CPU is processing an instruction, as opposed to just loading or saving data.

The full modification allows RAM between 8000 hex (32768) to BFFF (49151) to be used for machine code, with any extra RAM between C000 to FFFF being used for data only. While allowing the RAM echo / shadow to continue in the C000 to FFFF area (accessed when /M1 indicates the CPU is reading an instruction) so that the ULA and CPU can work together to produce the display from the display file.

More technical info here and here;)

Mark

stevenmcdonald
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Re: HOT-Z Keys

Post by stevenmcdonald » Tue May 30, 2017 12:39 am

Hi Greg!

Good news for you my friend!!

I read your post a few months ago and promised I would reply to you...

I have taken a good number of hours today to get this for you - I owe you it in many ways!! ;-)

Back in the late 80's yourself and Fred Nachbaur were good enough to send me over some hardware, software , manuals etc.

We were discussing distributing my games over the pond and other hardware matters regarding Wilf's true HRG WRX16 system.

Anyway, I have kept all that stuff in a big folder up the attic ... so here it is...

The original 50 page manual scanned, cleaned up and ready for release! (I actually think now this is Fred's copy as it seems to have his annotations on it in his handwriting.)

Perhaps someone can help me?

I am trying to get a working 16K version of HOT-Z II.

There was a 16K version, a 64K RAM Pack version and a relocated port that Fred did called HI-Z.

The user manuals etc are all included in this zip I shall link to on my website hosting area.

I retrieved the 16K version today from tape but it seems corrupt when I tried to copy it.. Anyone have a working version out there?

Enjoy.

Steven McDonald.

link:

http://www.pictureviewerpro.com/hosting ... t-Z_II.zip

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mrtinb
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Re: HOT-Z Keys

Post by mrtinb » Tue May 30, 2017 12:27 pm

Wow. Thank you. Very much appreciated.
Martin
ZX81, Lambda 8300, Commodore 64, Mac G4 Cube

stevenmcdonald
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Re: HOT-Z Keys

Post by stevenmcdonald » Tue May 30, 2017 1:10 pm

Welcome!

Anyone located the fabled 16k version yet!

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sirmorris
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Re: HOT-Z Keys

Post by sirmorris » Tue May 30, 2017 9:00 pm

Steve, could you post a nice wav type recording of the 16k tape version? Maybe if there's an issue with dropouts or something then they could be patched up. I seem to remember that there are some very talented tape reconstructeurs on the board ;)

There is a program called TAPESCRAPE which will dump the content of tape to SD card directly without involving save/load. I don't imagine it will perform miracles, nor magic maybe not even a convincing parlour trick but who knows. Running it a few times over the program might show where the corruption occurs.
--=== ZXpand+ ... A more moderner all-in-one upgrade solution for ZX81 ===--
* SD/MMC storage * 32K Hires-capable RAM * AY sound chip * Joystick port * Serial *
* BASIC enhancements - plug & play * Reset button * Auto-boot facility *

stevenmcdonald
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Re: HOT-Z Keys

Post by stevenmcdonald » Wed May 31, 2017 12:29 am

Hi sirmorris!

I don't actually think my copy is corrupt as such it's
More like well it's weird.. it's like the master copy has data stored in the printer buffer and if you
Rand usr 836 the tape it comes up c/0 as expected but there is no code to view as such due to the way it's been saved.
In short it's hard to copy.
It should work but it doesn't! Hmm may need to test with ZXpand patched out and see how that does..

Pressing the S key saves out to tape a new version but with ZXpand it saves it to SDCARD but seems to crash when starting. Up .
I did try tapescrape 5.1 yesterday but that did weird things also saving the loader as hotz whilst bigrem recovered fine.

I'll get together a wav copy for you to examine..

What format do you want - 22khz mono 8 bit?

Never thaught to run the wav through my own decoder program either..

More experiments tomorrow then... I'll get a wav for you anyway.

Thanks.

Steve

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