That is all already written right in the reference I linked you to. If you don't understand the answer, how is that anyone else's fault? It's written in English not Swahili. It explains exactly every step of the answer the question you *just* posed about how the FC error actually happens, in detail.
And yes you were shown "what it would take to make it happen", in that it explains the device driver hooks in the rom. That is your necessary starting point. Invent whatever kind of communication protocol you want, and write device emulator code on the pi and device driver code on the m100 to implement that protocol, and the reference shows the secret of how to get the rom to use it. -- bkw On Feb 14, 2018 8:22 AM, "VANDEN BOSSCHE JAN" <jan.vandenboss...@vivaqua.be> wrote: > > You did recieve a very thorough answer. That it won't work, and why not, > > > > Sure. And meanwhile, I understood why not. But not thanks to the replies I > got here, but thanks to the reply on the Raspberry Pi group. > > > > Thorough answer ? Maybe to you, but not to me. > > > > Anyway, AFAIK, nobody tried it. > > > > Like everybody was convinced that heavy objects > <https://en.wikipedia.org/wiki/Galileo_Galilei#Falling_bodies> fall > faster than light ones, untill some guy climbed a tower > <https://en.wikipedia.org/wiki/Simon_Stevin#Geometry,_physics_and_trigonometry> > and tried it. > > > > > and what it would take to make it work. > > > > Can't remember reading that. > > > > > All that will happen is BASIC will jump to a particular address, which > jumps to the FC error. > > > > Does it jump to FC Error directly, or because it checks that there is > nothing hanging on the system bus? That could be determined by looking at > the ROM-code. But again, AFAIK, nobody checked that. (at least, nobody > posted it) > > > > So, you probably need software to prevent the FC error, just like the > driver from the DVI. Would that be difficult to write? Hasn't anybody > dis-assembled the code for the DVI? You'd only need the video-portion. > > > > Greetings from the TyRannoSaurus / Jan-80@work > > > > *From:* M100 [mailto:m100-boun...@lists.bitchin100.com] *On Behalf Of *Brian > White > *Sent:* dinsdag 13 februari 2018 17:25 > *To:* m...@bitchin100.com > *Subject:* Re: [M100] List of wanna haves > > > > You did recieve a very thorough answer. That it won't work, and why not, > and what it would take to make it work. All that will happen is BASIC will > jump to a particular address, which jumps to the FC error. > > > > -- > > bkw > > > > On Feb 13, 2018 8:53 AM, "VANDEN BOSSCHE JAN" < > jan.vandenboss...@vivaqua.be> wrote: > > > > I have asked the Raspberry Pi community to help me with the construction > of a DVI-like video-output device. I made the assumption that the DVI was > only a terminal. Both from the response here, as there, I understand now > that this combination is far more 'intimate' than I presumed. > > > > https://www.raspberrypi.org/forums/viewtopic.php?p=1271713#p1271713 > > > > I hope that the response given in the above thread helps and incites > people, with far better and more knowledge of the processes and controllers > involved, to pick up on this project and propose the parameters for a > video-interface. > > > > As far as I understand, the driver loaded from the DVI re-maps the video > controller of the M100 towards the one in the DVI, where new tekst and > graphics are generated. The 4K memory in the schematics is obviously the > video-RAM, where 40x16 text (640 bytes) and 240x128 points (3840 bytes) > reside. I suppose text and graphics do not reside in different memory > locations. (because it doesn't fit...) > > > > Anyway, contrary to what I thought before, we will probably need to > activate the SCREEN 1, 1 directive with software on the M100 itself. But > that software does not need to be as big as the original driver, because no > disk-routines are necessary. > > > > I'm sorry if I sound presumptuous, and I apologise if I impose on people's > limited time, but I think this is a project worth pursuing. > > > > (And I still didn't get an answer about the experiment I proposed, below.) > > Greetings from the TyRannoSaurus > Jan-80 """"" > > @ work ( @ @ ) > --------------.ooo--(_)--ooo.--- > > *From:* VANDEN BOSSCHE JAN > *Sent:* vrijdag 9 februari 2018 09:47 > *To:* 'm...@bitchin100.com' > *Subject:* RE: [M100] List of wanna haves > > > > .. .. (As I'm accessing this list from 2 different locations, > > .. .. and my yahoo-postings aren't always visible to everyone, > > .. .. I have repeated the question I send below) > > > > I'm sadly enough not that technical, so I can't draw the same conclusion > from the link below. Can't that be confirmed from the ROM BASIC > dis-assembly too? Without a DVI connected and drivers loaded, what does > SCREEN 1,1 do ? > > > > Anyway, even if it is wrong: would it take a lot of effort to re-write > only the display output portion of the DVI-drivers? That way, development > could start on a software solution for the video-output via the system bus. > I had thought of using the GPIO-pins of a Raspberry Pi for that. As the > R.Pi can also emulate a TPDD, you'd have a virtual DVI replacement, there. > > Greetings from the TyRannoSaurus > Jan-80 """"" > > > @ work ( @ @ ) > --------------.ooo--(_)--ooo.--- > > *From:* M100 [mailto:m100-boun...@lists.bitchin100.com > <m100-boun...@lists.bitchin100.com>] *On Behalf Of *Brian White > > > *Sent:* vrijdag 9 februari 2018 01:59 > *To:* m...@bitchin100.com > > *Subject:* Re: [M100] List of wanna haves > > > > That won't work. I don't remember where I read this, but I read that the > system rom has calls for certain functions but they are just stubs. The rom > only contains the stub of a call that says "open CRT: for writing" which > just says go to some address and do whatever that address says. Normally > that address just points to the address for the built-in routine to return > the FC? error. But if dvi dos is installed then that address contains the > address of the routine in dvi dos to actually do something. > > Aha, here's where I read it. Start on page 257 > https://archive.org/details/InsideTheTrs80Model100 > > I can try it when I get home but we already know. > > -- > > bkw > > > > > > > > *From:* Jan Vanden Bossche [mailto:jan80...@yahoo.com <jan80...@yahoo.com>] > > > > how would you use it? > > > > To have a bigger screen to work on, when not on the move. Imagine, a > 17-inch old VGA monitor with 40 x 24 characters! HUUUUUGE! > > > > I have a question, for anybody having a DVI: > > Could you try the following: is it possible to operate a Model T hooked up > to a DVI, with the DVI ready to accept input and disk commands, but the > Model T without the driver software? I would think this is possible when > you boot up both machines, establish the connection, and then, while > connected, reset the Model so that it is no longer aware of it's > 'companion'. At that moment, enter BASIC and type SCREEN 1,1. That would > send all BASIC output to the DVI, right? Does it ? (thàt's the question) > > > > The above experiment would show if it's at all possible to run a > monitor-only part of a DVI, without loading software on the Model T to do > so. I hope, that the simple command SCREEN 1,1 does send some > screen-positioning code through the bus towards the DVI, even without the > drivers loaded on the Model T. If it does, some clever programming on the > receiving side could just give us the DVI/video-only device we seek. > > > > Greetings from the TyRannoSaurus > Jan-80 > > > ------------------------------ > > *From:* Mike Stein <mhs.st...@gmail.com> > *To:* m...@bitchin100.com > *Sent:* Thursday, 8 February 2018, 3:49 > *Subject:* Re: [M100] List of wanna haves > > > > Just curious: how would you use it? > > > > m > > > > ----- Original Message ----- > > From: "Randy Kindig" <randall.kin...@gmail.com> > > > > > Agreed! Just the video part of the DVI would be high on my list > > > > > > VIVAQUA et HYDROBRU ont fusionné. > > VIVAQUA est votre société d'eau en Région de Bruxelles-Capitale. > > VIVAQUA en HYDROBRU zijn gefusioneerd. > VIVAQUA is uw waterbedrijf in het Brusselse Hoofdstedelijk Gewest. > > Rejoignez-nous sur Facebook - Volg ons op Facebook > > > > DISCLAIMER > > Pensez à l’environnement, n’imprimez cette page et ses annexes que si > c’est nécessaire. Ce message électronique, y compris ses annexes, est > confidentiel et réservé à l’attention de son destinataire. Si vous n’êtes > pas le destinataire de ce message, merci de le détruire et d’en informer > l’expéditeur. Toute divulgation, copie ou utilisation de ce mail est dans > ce cas interdite. La sécurité et l’exactitude des transmissions de messages > électroniques ne peuvent être garanties. > > Denk aan het milieu; druk deze pagina en de bijlagen alleen af als het > nodig is. 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