Setting Up a dual boot rom

Upgrade or replace the ROM.
Glorfindeal
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Re: Setting Up a dual boot rom

Post by Glorfindeal »

I'm using an app call Hex Fiend on the Mac. That option doesn't exist. I may have to find another hex editor.
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PhilC
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Re: Setting Up a dual boot rom

Post by PhilC »

Glorfindeal wrote: Sat May 09, 2020 9:07 pm I'm using an app call Hex Fiend on the Mac. That option doesn't exist. I may have to find another hex editor.
Ah right ok, no idea about that app, although may download it and try it on my iMac if its any good.
If it ain't broke, test it to Destruction.
Glorfindeal
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Re: Setting Up a dual boot rom

Post by Glorfindeal »

Good! Download it and figure out how to do a byteswap and let me know. :lol:
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Re: Setting Up a dual boot rom

Post by Glorfindeal »

Am I allowed to attach my rom file so you can take a look at it?
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exxos
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Re: Setting Up a dual boot rom

Post by exxos »

Glorfindeal wrote: Sat May 09, 2020 11:33 pm Am I allowed to attach my rom file so you can take a look at it?
You can upload files, but you may have to rename the extension to txt or something.
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rubber_jonnie
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Re: Setting Up a dual boot rom

Post by rubber_jonnie »

I really want to get my hands on some erasable 27C4096 PLCC chips, and even if they are only UV erasable and not electrically, it means you don't bugger up an entire chip to do a test.

At least that way I can verify any dual TOS images I make since this whole thing of making a dual TOS ROM is new to me too.

And since the non-erasable variants are not exactly cheap, I'll at least know I have a good image before committing.
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800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
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PhilC
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Re: Setting Up a dual boot rom

Post by PhilC »

@rubber_jonnie do a search for hn27c4096 on Ebay and you'll find some Hitachi ones. These are the types I use.
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rubber_jonnie
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Re: Setting Up a dual boot rom

Post by rubber_jonnie »

PhilC wrote: Sun May 10, 2020 6:27 pm @rubber_jonnie do a search for hn27c4096 on Ebay and you'll find some Hitachi ones. These are the types I use.
Cool, thanks I'll give that a go.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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JezC
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Re: Setting Up a dual boot rom

Post by JezC »

@rubber_jonnie There was an ebay seller recommended on this forum a while back...I've ordered 5 of them but have not yet tested them. :roll:
A bit cheaper than the OTP versions....

I've ordered them to test the images prior to risking them in the OTP version (and also for a couple of applications where the speed of teh UV EPROMs is fine).

https://www.exxosforum.co.uk/forum/viewt ... =10#p31876

Biggest problem will be the delay before you can test with them :(
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rubber_jonnie
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Re: Setting Up a dual boot rom

Post by rubber_jonnie »

JezC wrote: Sun May 10, 2020 6:33 pm @rubber_jonnie There was an ebay seller recommended on this forum a while back...I've ordered 5 of them but have not yet tested them. :roll:
A bit cheaper than the OTP versions....

I've ordered them to test the images prior to risking them in the OTP version (and also for a couple of applications where the speed of teh UV EPROMs is fine).

https://www.exxosforum.co.uk/forum/viewt ... =10#p31876

Biggest problem will be the delay before you can test with them :(
Yeah, Australia unfortunately, so China for all intents and purposes! Will see what I can find.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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