15 replies to this topic

[Bob Vila]

i think that we have enough brains in this forum to develop a virtual casio (like the vti) which would emulate the cfx, afx, and classpad, maybe older ones too.

[AlephMobius]

Good idea. I have no idea how you would do this. I think you would need to know ASM and how machine language works. I would be willing to help but I really have no idea how to start. I know you would need a ROM image, can we get that? It seems to me that you would just need to look at the program (The ADD-IN you are running or part of the ROM itself or whatever is happening) and interpret each machine language instruction. Anyways, someone will no how to do it exactly so I will stop speculating.

[Bob Vila]

I know you would need a ROM image, can we get that?

i think that martin had a thing for rom dumping on his site.

[huhn_m]

1. There was a thread about romdumps. search the forum. superna or so collected some.
2. It is not possible to write an emulator that uses that casio programs until we know ALL features of the hardware EXACTLY. else they won't work. so you'll still have to discover a LOT of things. In my mind it is
NOT possible till now.

[Bob Vila]

In my mind it is NOT possible till now.

so it is possible?

[huhn_m]

at all yes but definately not with our knowledge.
We don't know what methods the cas OS uses we don't know.
We don't know bugs of the calc that may be used by the OS. etc ...

You should be an excelent hacker to figure this out in order to make an emu 100% compatible with the casio OS.

[betoe]

I investigate about the hardware of the calculator, especially the micro processor. I found this information (not contains the instructions set of the uP , but worse is notthing). The websites are:


http://www.necel.com...57/DTI57LUZ.pdf
http://pocket-viewer...r/files/v30.pdf

I know about uP, because I study electronic engineer, i hope that this information help to this topic. If you have any doubt, i will investigate about that topic and tell you by this forum.

[XYZ]

I've never attempted an emu but wouldn't it be really hard to make an emulator for so many different processors? The AFX might be easy enough, there being quite a lot of talented programmers, documentation, and a common cpu etc but for the cfx and older fx's there really isn't much known about the systems, is there? As you said huhn-m... It may be easier to make an emu for one calc then others if there is support.... Just my $00.02 - XYZ

[AlephMobius]

VTI can emulate so many different calculators because the 73-86 all use the same processer and the 89/92/v200 use the same processer. Are the AFX,FX, and CFX CPUs all different? The AFX CPU is based on the 286 so shouldnt that make it a lot easier? VTI is open source in case you want to look at how they did some things.

[Andy.Davies]

what is VTI and do you know where i can get it?

[AlephMobius]

VTI is an emulator for TI calculators. You can find a description, review, and download link at :http://www.ticalc.org/archives/files/fileinfo/84/8442.html. You should also be able to find the C++ source there as well. You will need a ROM image which you can get from TIs website or if you want an earlier version (on the latest is on the site) youi can email ticares AT ti.com and request that they send you one. Also, its only legal to own a ROM if you own the origional calculator.

[huhn_m]

Well the CFX should be a problem since it is all dynamic. I think it has nothing got to do with AFX / FX but AFX & FX are nearly the same.

The problem are the hardware interrupts that are made by the bios. In fact all you do writing an emulator
is to rewrite the bios and its interrupts but we know to few of those to do so. THis is the problem. I believe
,and have also tested it for some, that the AFX has interrupts for basic file use, com-port etc ...

The problem is that if these interrupts are set up by the bios you MUST rewrite them in order to make the
System work with the casio programs. For the comport you would have to use a Pipe through which another com programm will comunicate and so on. Thats pretty difficult.

[2072]

interrupts for basic file use ?

[TomL_12953]

AlephMobius, the AFX is based on the 80186, not the 80286, The '186 has most of the instructions of the '286. The exception being that the protected mode instructions are not included.

[superna]

yea in our forum we are 3 to know esactly how to really emulate the calc : Me, Mastermage et Whyp

Whyp is dooing an emulator, he arrived to launch code but not booting the calc, mastermage arrived to same point.

I found on the internet a machine emulator : MESS (mame version for machine) but i don't know how to add a machine...

Yea it is complicated because we must emulate RAM and processor (quite easy) but after you have the screen, the flash, the ROM, Interuptions and I/O ports to control !

The screen is esay to emulate, the flash and rom is ok aswell but eh I/O ports are difficult to emulate because we don't really know how they work lik ethe interuptions to execute and when !

So i think I answered to your question...

[betoe]

The bad thing is that Casio and NEC don't reveal information of the hardware (CPU interruptions, etc...). The AFX is a very good calculator but casio dont bring emulators for users.

I think that they must give tools for the calculator use, I dont know very well if other companies like TI or HP do it.