im looking for an emulator that does the 16 bit 32k upgrade mod

[xxx]

does one exist? ive had a look and cant find one.

[HOME AUTOMATION]

Cory Burr calls Win994a a simulator... casual users probably don't make much of a distinction...

 

[xxx]

ok, cool. so what about rom carts? does this speed them up too?

[+arcadeshopper]

Pretty sure mame does as well

 

[+RXB]

How is 16 bit RAM a upgrade when this kills off SAMS 1 Meg of memory?

 

This is like a really fast RAMDISK, but really really dinky space available.

 

Not to mention most programs will not work right due to speed of faster processing RAM so chip timing fail and crash.

 

As long as you stick with Assembly and limit the size of anything using this mod it is fine.

 

So end result is not really a upgrade as more of a side grade nitch change.

[senior_falcon]

 

Not to mention most programs will not work right due to speed of faster processing RAM so chip timing fail and crash.

 

 

This is not correct. The only program I have ever seen that does not run properly is Tennis. There may be others, but most programs work fine.

If you don't have the SAMS card then where is the problem? I am not troubled by this in the least.

[+RXB]

I would like to see more SAMS programs like my IN THE DARK game that used 660K of SAMS.

 

It would be cool to see some Assembly games that use almost 1 Meg of SAMS RAM!

[JB]

Is a 16-bit SAMS design technically possible? You know, get the best of both worlds.

[Tursi]

ok, cool. so what about rom carts? does this speed them up too?

No, it only speeds up access to the 32k RAM.

[apersson850]

I don't have any SAMS 1 Meg thing. Why does an internal 32 K RAM prevent SAMS to be used? What's the technical reason?

 

If you have a ROM cart and the kind of internal memory expansion I have, which is really 64 K RAM, it's technically possible to run the cart ROM faster too. I can copy it to my fast RAM, then enable RAM instead of cartridge ROM at the cartridge address space. But it takes the cartridge is no more than 8 K for that to work, and loading the thing may be somewhat tricky.

[mizapf]

This is not correct. The only program I have ever seen that does not run properly is Tennis.

 

TurboPasc'99 is another example. It tries to verify whether it already loaded the support routines, expecting a (FF00)* pattern in RAM. The 32K expansions show a (00)* pattern. This can be checked in MAME.

[+arcadeshopper]

I don't have any SAMS 1 Meg thing. Why does an internal 32 K RAM prevent SAMS to be used? What's the technical reason?

 

If you have a ROM cart and the kind of internal memory expansion I have, which is really 64 K RAM, it's technically possible to run the cart ROM faster too. I can copy it to my fast RAM, then enable RAM instead of cartridge ROM at the cartridge address space. But it takes the cartridge is no more than 8 K for that to work, and loading the thing may be somewhat tricky.

 

32k is in a memory space

sams exists in the same space plus the rest of the ram elsewhere

same operates by banking in 4k at a time of the SAMS memory into part of the 32k space, so it has to be the 32k ram l

..

basically like parking two cars in the same space, doesn't work

 

Greg

[apersson850]

I see. It would work with my kind of internal memory expansion, then, since I can control 8 K banks with CRU-bits. If I disable internal RAM in the standard RAM expansion address range, then the computer will fall back to using the standard 32 K RAM expansion, if there is any.

[+Lee Stewart]

I see. It would work with my kind of internal memory expansion, then, since I can control 8 K banks with CRU-bits. If I disable internal RAM in the standard RAM expansion address range, then the computer will fall back to using the standard 32 K RAM expansion, if there is any.

 

Or, as in this case, the SAMS card, 32 KiB of which becomes the standard RAM expansion.

 

...lee

[+RXB]

 

Or, as in this case, the SAMS card, 32 KiB of which becomes the standard RAM expansion.

 

...lee

You mean PASS mode in the SAMS?

 

PASS mode is normal default SAMS mode when you fire up TI99/4A & P-Box on power up.

 

Now if you leave the P-Box on and do a TI99/4A power up only, what ever SAMS pages are set stay set.

 

This is why in RXB you can turn off the Console and go back to XB none of the SAMS pages have changed.

 

Since RXB 2015 I removed the initialization routines of the SAMS as they were not really needed.

Edited February 27, 2019 by RXB

[apersson850]

I took a look at the thread about the SAMS card, so now I know how it works. The 74LS612 memory mapper is a handy device.

It's of course non-standard, but since my internal memory design allows paging RAM pages of 8 K in or out, and those that are paged out will allow access to whatever is there otherwise (external RAM expansion, console ROM etc.), it could easily co-exist with a SAMS card. Run your program in up to 24 K internal 16-bit RAM (note that this allows you to place both code and workspaces wherever you like - they are equally fast), and open an 8 K window to two SAMS pages at a time.