EMS memory is mapped into a 64k section of Upper memory but doesn't reside there. It is actually a window that allows you to access the memory as DOS memory. I'll look at your configs now.

Do you need SETVER? Disabling it should buy you some memory.

Also, setting LASTDRIVE in config.sys to the last drive you use should buy more memory.

I think your system's too small for disk compression, but if you get a utility such as PKZip or DOSRAR, you can create batch files to temporarily decompress programs, run them then clean up afterward by recompressing them and deleting the uncompressed copy. That should allow you to put more stuff on your hard drive.

amstradus wrote on Today, 19:40:

Harry Potter wrote on Today, 17:11:

No. Upper memory is the memory available to DOS between 640k and 1024k. EMS memory is extra memory that is outside main memory but gets mapped into a piece of the first 1MB of memory. BTW, I don't like your setup's used memory. I ask you for your config files and can recommend you use the CTMOUSE driver available at https://dosprograms.info.tt/indexall.htm under the Utilities section. It is much smaller than the Microsoft mouse driver.

Hmm... I'm afraid I'm a bit out of my depth. So where is the EMS memory mapped? I actually don't have a mouse. I don't intend to use a mouse for the sequencing software, though I'm sure I will later. I've only been able to locate that mouse adapter from that guy in Greece. Here is my config file:

https://postimg.cc/f3fsrJ9y

Normally, EMS lives at D000-DFFF, or E000-EFFF.

On an XT, there is usually 'NOTHING AT ALL' attached to the memory bus at those addresses.

BECAUSE you have an XTIDE installed, the XUB will be living at one of them. Whichever is in use, the EMS card should be configured at the other.

D000 and E000 are both 'well above' the top of the base 640k, which ends at AFFF, iirc.

The usual DOS memory map looks like this:

[0000-AFFF {640k}]
[B000-BFFF Reserved for MDA and CGA/EGA graphics]
[C000-CFFF reserved for VGA ROM BIOS]
[D000-DFFF is usually free for use]
[E000-EFFF is usually free for use]
[F000-FFFF is the system ROM BIOS]

wierd_w: you made a mistake: DOS memory ends at $9FFF. $A000-$AFFF is the EGA/VGA graphics buffer, though there are utilities that can make that area available for text DOS applications.

If you want, there's a utility called 2M. It can increase the capacity of floppies and should require a small memory footprint. You can find it at http://www.retroarchive.org/garbo/pc/diskutil/index.html.

Harry Potter wrote on Today, 21:33:

I think your system's too small for disk compression, but if you get a utility such as PKZip or DOSRAR, you can create batch files to temporarily decompress programs, run them then clean up afterward by recompressing them and deleting the uncompressed copy. That should allow you to put more stuff on your hard drive.

Says you. I've run Double Space on a 4,77 MHz 8088 PC/XT no problem (Siemens-Nixdorf 8810 M35).
There was no performance penalty.
Rather the contrary, drive compression even helped performance with the slow MFM HDD.
CPU utilization was no big deal, either, no noticeable slow down.
Now, the OP's Amstrad PC1512 with 8086 and 8 MHz is about 4x as strong.

Anyhow, memory consumption is a valid argument, I think.
Double Space/Drive Space needs a few dozen KB of RAM..
So it's not for everyone. Users with an UMB RAM card are better off here, I think.

Edited.

PS: I forgot to mention. Double Space or Drive Space have a 2GB limit.
So it can't be used to increase capacity of, say, an 2 GB HDD.
It also doesn't like FAT32, I think.

Oh, but Stacker should be better, and JAM should both be better and require a low memory footprint. 😀

Harry Potter wrote on Today, 19:54:

Do you need SETVER? Disabling it should buy you some memory.

Not sure about this. This is a compatibility driver to make sure software designed for older dos versions runs on the newer dos, no? I would think this was important for my needs, seeing as I intend on running some older software, but maybe you can tell me if it is necessary.

Harry Potter wrote on Today, 19:56:

Also, setting LASTDRIVE in config.sys to the last drive you use should buy more memory.

Thank you. I just have the A and B floppies and the XTIDE at C. So then set LASTDRIVE=C ?

It is. You probably should keep it. An idea: Maybe you should create alternate boot disks with just the software you need for a session.

Yes.