rant on
It always surprises me that anyone would do an 8085 assembler or
disassembler and not implement the undocumented instructions. I mean
they're there, everyone knows about them, it has been decades, the
instructions were fully implemented and stable, they're not hard to find
and as you're
On Sun, Feb 19, 2023 at 12:34 PM Stephen Adolph
wrote:
> Yah I'm not sure it is actually doable, in a reasonable amount of time
> effort.
> It is hard to separate data tables from code.
>
> I found one disassembler that was capable of labeling, and tracing code,
> but it did not support undoc
And can I just say that Ken completing his NEC PC-8201A fully commented
disassembly is absolutely amazing! Thank you, Ken, for your diligence.
The help this will give me on filling in the gaps in my Memory Map Database
is huge.
On Thu, Feb 23, 2023 at 7:09 AM Stephen Adolph wrote:
> thanks
thanks Ken, this is very helpful. I never like to quit something that is
part way done, so I'll take a look at it again.
Right now I am part way through the MVT100 PC terminal app, going well.
On Thu, Feb 23, 2023 at 12:11 AM Kenneth Pettit wrote:
> Hey Steve,
>
> I don't know if you are still
Hey Steve,
I don't know if you are still trying to get SuperROM ported to PC-8201
or not, but I have merged in all of my M100 disassembly comments into
the PC-8201 disassembly and was able to find *most* of the calls you
identified below.
Note however the following:
1. The encoding for
The floating point encoding in the NEC is much different than the other
models. The M100/102/200, etc. use BCD encoding, but I never could
figure out how NEC was encoding it.
Some bizzare encoding where single precison ZERO is represented as 00h
00h C7h 00h
Ken
On 2/19/23 12:33 PM,
Yah I'm not sure it is actually doable, in a reasonable amount of time
effort.
It is hard to separate data tables from code.
I found one disassembler that was capable of labeling, and tracing code,
but it did not support undoc opcodes, so it wasn't a good disassembly to
use.
I think all the
Hey Steve
So this is definitely going to be pretty involved. As people have already
stated, the math subsystem of the Model 100's vs. NEC 8201's version of
BASIC is pretty different. Going through that list of addresses and just
looking at the instructions being done by the M100 for each as
Hi Steve,
Well first of all, it's awesome you've got a renewed interest in this
little project!
One resource you might also find helpful is the ModelT Memory Map
Database:
https://www.web8201.net/default.asp?content=modelt_memorymaps/mapview.asp
I'm also willing to assist with the conversions on
Hey Steve,
Looks like the NEC and M100 math routines are a fair amount different.
I have started a task of annotating the NEC VirtualT disassembly listing
with the hand-coded changes I made to the M100 disassembly. We'll see
how far I get along this path (There are a LOT of additions I made
, February 18, 2023 2:07 PM
To: m...@bitchin100.com
Subject: Re: [M100] Super ROM for NEC
Reviving this thread.
SuperROM uses RST1 to make "trampoline" calls to the main ROM.
I've gone through all of the RST1 calls that SuperROM makes to the M100 main
rom.
Most convert well.
The
Reviving this thread.
SuperROM uses RST1 to make "trampoline" calls to the main ROM.
I've gone through all of the RST1 calls that SuperROM makes to the M100
main rom.
Most convert well.
The really big gap is that the math routines are very different in PC-8201.
If there is anyone motivated to
Exciting! (Said a nerd.)
On Monday, July 19, 2021, 12:40:36 PM EDT, Stephen Adolph
wrote:
Update for the list.
Making progress!Using a combination of tools - python, DASMX140, and excel,
I've been able to get a pretty complete "structural disassembly" of the Super
ROM.
>From here, it
Update for the list.
Making progress!
Using a combination of tools - python, DASMX140, and excel, I've been able
to get a pretty complete "structural disassembly" of the Super ROM.
>From here, it is apparent how the main ROM calls are used, and what
memory locations are used.
There are about 450
hah, well... I did get a start and it is, at first glance, not what I
expected!
The trampoline is very different, so I am piecing together how that works
first.
Still, a useful mental exercise. I think the end goal would be great.
On Wed, Jul 14, 2021 at 4:33 PM Gary Weber wrote:
> I love this
I love this whole idea!The ROM address conversion would be the easy
part, if we can call anything "easy" regarding this. :)
It's the upper RAM addresses that could be quite tricky. There's some
differences in the hook table and then even more differences that don't
seem to be well
I've disassembled and taken a quick look. it is quite different than "MO"
would have done, but the trampoline is clear.
(using DASMX140, which seems to be a really good disassembler!)
On Mon, Jul 12, 2021 at 1:30 PM John R. Hogerhuis wrote:
> I think it very doable. It comes down to the
On Mon, Jul 12, 2021 at 11:02 AM Brian K. White
wrote:
> On 7/12/21 1:30 PM, John R. Hogerhuis wrote:
>
> > Definitely worth it given SuperROM being the best ROM :-)
> >
> > -- John.
>
>
> I wish you wouldn't be so coy and cryptic about your stance on what the
> best option rom ever released
On 7/12/21 1:30 PM, John R. Hogerhuis wrote:
I think it very doable. It comes down to the completeness and quality of
the disassembly and identifying all jumps into the BASIC ROM including
indirect or computed jumps and mapping them from M100 to NEC.
The option ROM skeleton and trampoline
I think it very doable. It comes down to the completeness and quality of
the disassembly and identifying all jumps into the BASIC ROM including
indirect or computed jumps and mapping them from M100 to NEC.
The option ROM skeleton and trampoline stuff is probably the best
understood and easiest
I can only say that if you think you can do it, then I think you can do it.
It certainly would be cool.
--
bkw
On 7/12/21 8:30 AM, Stephen Adolph wrote:
Noting that SuperROM has never been found (or never released?) for
NEC, it seems to me given what I know about making applications run on
Interesting! Was discussing the availability of a SuperRom image for NEC
just this past weekend on Discord with @Fezzler and I was wondering how
difficult it would be to convert.
Your description of the process is somewhat 'greek' to me so I'm guessing
that I'd need to level up a bit to be able
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