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Re: Supporters for Reverse Engineering needed

2008-08-12 by magmusic75

Hello I fully support your effort. I think that somehow getting the 
floppy OS (Disk Overlay) onto an EPROM and then having it programmed 
so the EII looks for the OS on the EPROM or some kind of flash memory 
would be great. Then add one new feature to the (SPECIAL) command set 
called "Serial Control". Now in this feature you would hand over 
control of the EII to a PC or Mac Running some custom software 
control application. This app should have the standard EIl features 
such as "Disk, Voice Definition Ect... but at a minimum it would just 
be great to be able to power up the EII right from rom.
 Anyway as I said I fully support this effort and would be glad to 
pay for these new features! As would many other I suspect.

John

======================================================================

--- In emulatorII-list@yahoogroups.com, "hoschi1103" <totti@...> 
wrote:
>
> Hi all,
> 
> there were no news from me for a long time, as I'm always busy doing
> other things.
> 
> Disassembling of both ROM nearly finished. Main ROM does contain
> memory and peripherial init, disk I/O, some serial port stuff (see 
1st
> request below) and a really big (for ancient times) table of initial
> data for all devices in the system. Scanner ROM holds all I/O stuff 
as
> described in the service manual and some system init, too.
> Interesting solution for system init: Main CPU and Scanner CPU start
> async, Scanner CPU turns LEDs on and waits for Main CPU. Only if 
Main
> CPU passes the peripherial init, it signals Scanner CPU. Scanner CPU
> then turns off LEDs and just displays "Insert diskette". That's how
> the system assumes everything is ok, a reason for defect memory not
> detected, as the main CPU only fills memory with 00 without really
> checking.
> 
> As the ROM holds only basic functions, everything else is done via 
the
> overlays from any diskette. That leaves some perspective to play
> around :D. I finally received my Catweasel board, so next thing
> is to write a char reader to dump the disks to PC and start 
analyzing
> them.
> 
> After that: Proof that external device or software in fact is taking
> full control over EII and controls everything like EII itself would
> do, by dumping communication on the serial port. If it does like 
this,
> as I assume from the code I've seen so far, the EII can be 
controlled
> by any device with a serial port interface :-) (Assuming you have 
all
> neccessary port interfaces and some code to come...). I always 
thought
> that it must do so, because that's the only explanation why SDII and
> the external CD-ROM (on the other port) did work at all.
> 
> Now for my requests:
> 1. Does anybody have ROM images earlier than the ones available 
here?
> Please provide them, it could help a lot. The main ROM still 
contains
> the remains of the serial monitor mentioned in the service manual,
> only some bytes at the beginning are NOPed out and it will RET
> immediately. I suppose it was used by setting the NMI to it to debug
> the system.
> 
> 2. Can anybody make a portlist from the schematics? I tried myself,
> but my knowledge (and my rooms walls) is not big enough to draw it 
out.
> 
> 3. Does anybody know a serial port monitor for PC (Linux or Win) 
that
> only records signals coming in, without caring for any protocol? I
> used to do it with my old NEC serial linemodem analyzer, but it only
> outputs to its CRT, which does not help much.
> 
> That's all for now,
> Hoschi
>

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