exxos's Atari, Amiga & retro forum

exxos wrote: 11 Sep 2018 17:42 I guess patched code could check the register to see if a write fails or something.. Then it knows if its running on the new MMU or not... or just separate patched versions of software :shrug:

Yeah that's no problem. Demos can easily check to see if the functionality is there, and new TOS images could set cookies.

exxos,

you will be down in the hall of fame for someone to reproduced an atari stfm,

it will more than likely be in someones collection in 25 years time, perhaps in a perspex box for viewing purposes only :)

passed down through the generations :) until no one even knows what its for :)

dave

KyleB wrote: 28 Aug 2018 01:11 Been thinking a while about the ram being a falcon board. Not sure that's a good idea, I mean I get the basic principle - all falcs are 14mb these days it seems so why not recycle - but not sure that these 4MB boards are going to be all that plentiful anymore after 25 years of being chucked in the bin.

Is there not some 4MB ramchip that will work in an ST circuit? Or even just one 4mb simm, seems easy enough to find on ebay especially laptop stuff.

The one thing that the ST hasn't got which would be highly useful would be an expansion port to add peripherals to.

The discussion about the second CPU got me thinking about how you could create a generic expansion system memory mapped into the ST address space. Then occurred to me that we do actually have one, though it's read-only (unless you use tricks) and can't generate an interrupt: the cartridge port.

Of course, the new STF would have to be fully backwards compatible with cartridges but I was wondering what control lines would be needed to be added somehow to give full write functionality and allow it to generate an interrupt. Would it be few enough to use a standard connector and short ribbon cable from an additional externally accessible port?

Of course, one of the great benefits would be that TOS tries to boot from the cartridge, so a ROM could be used by any peripheral it initialise it out of the box, as it were.

I could see it being useful not only for such things as ethernet devices (faster than NetUSBee as it'd have interrupts and not use "write using read" hacks) but possibly reasonably fast USB or other specialist devices. It could open up all sorts of possibilities without having to open the case.

Any thoughts as to whether this might be feasible?

I agree the ST need a proper expansion bus.
I put on ont he 68020 card me and Juliusz are working on. It has all the 68020/30 signals plus router BR/BG and 7 IRQ pins (that runs to the CPLD which will then trigger an level 5 interrupt, which in a MSTE is the same as the SCC and on ST/STE is not used).
And we already have a few extra card in mind (and partially developed) like Ethernet.
May be a subset of this expansion bus could be used on the STFM remake in 24/16 mode instead of the 32/32 mode.
Rodolphe

stephen_usher wrote: 04 Oct 2018 20:28 The one thing that the ST hasn't got which would be highly useful would be an expansion port to add peripherals to.

VERSION 2.

https://www.exxosforum.co.uk/forum/viewt ... ?f=19&t=71

stephen_usher wrote: 04 Oct 2018 20:28 I could see it being useful not only for such things as ethernet devices (faster than NetUSBee as it'd have interrupts and not use "write using read" hacks) but possibly reasonably fast USB or other specialist devices. It could open up all sorts of possibilities without having to open the case.

There was already some talk about this last year.. http://atariage.com/forums/topic/267907 ... r-improve/

At some point I have considered reusing one of the 3 gnd connections to route a RW signal to the cartridge port.

Ooopps .... yep... version 2 ... I'll walk myself out ..

One of main goals of project is to add a range of IO ports.. in all that now unused motherboard space. Already been talked about lots over the past year.

Have been thinking a bit about the board and power being available.

When using several items with the board eg. Gigafile or other internal stuff that requires power would it not be advantageous to add another one or two power out pads next to CN2 i.e. a CN3.

That way if anyone wants to add in one or two internal items it can be powered easily

Yeah I can ad aux power connections anywhere ...