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skouris33
March 21st, 2014, 11:03 AM
Hi! Today I run the Norton SI version 6 diagnostic program on my 8088 and I discovered that my PC XT has almost 19,000 KB extended memory. I boot my PC with DOS 6.22 boot disk that I made with format /s command on a newer PC. Is this memory useful and accessible by my system or is it completely useless? Thank you

deathshadow
March 21st, 2014, 11:11 AM
If that's an 8088 that would be EXPANDED memory, not extended -- there's a difference. Extended memory is 286+ only.

EMS isn't used by a whole lot of normal programs, some spreadsheets will use it, databases will use it... The Wing Commander games will use it... that's about it.

skouris33
March 21st, 2014, 11:18 AM
Thanks for your reply! I'm sure that my processor is 8088 and that the message in the diagnostic program refers to the memory as extended. I also have this information: 'Bus type ISA: (PC/AT)'. Is this because of it that my PC can have extended memory?

Chuck(G)
March 21st, 2014, 11:31 AM
Even with an 80286, how can you possibly have 19MB of extended memory? (16 MB is the limit of 286 physical memory addressing). Extended memory is strictly a function of processor architecture--and the 8088 just doesn't have it.

Something is really hosed on your system--probably the program that's telling you all of this. Try another one--say, MSD from MSDOS 6.22.

skouris33
March 21st, 2014, 11:39 AM
Ok, I'll try it, thanks!

vwestlife
March 21st, 2014, 11:58 AM
I have seen diagnostic programs show large amounts of extended memory which doesn't exist on 8088 / NEC V20 machines, as well as cascaded IRQ controllers (i.e. PC/AT bus) which don't exist. You just have to ignore the false readings of features which cannot possibly exist on an XT-class machine.

Stone
March 21st, 2014, 12:41 PM
Ditto, ditto and... ditto! :-)

cr1901
March 21st, 2014, 12:54 PM
I'm going to hell for laughing while reading this thread... ahhh, the joys of old programs giving "accurate" information.

That said, like others have mentioned, something is probably wrong with the software you are using in how it detects memory.

This reminds me of numerous times that MS-DOS FDISK said that I had a partition of -700MB or so.

deathshadow
March 22nd, 2014, 06:10 PM
@vwestlife probably has it right. Most likely the diagnostic is getting confused by some sort of non-standard hardware -- it could even be too new to run on a 8088. @Chuck(g)'s suggestion of using MSD is probably best as it was one of the more... well behaved programs for getting system info.

vwestlife
March 22nd, 2014, 10:30 PM
@vwestlife probably has it right. Most likely the diagnostic is getting confused by some sort of non-standard hardware -- it could even be too new to run on a 8088. @Chuck(g)'s suggestion of using MSD is probably best as it was one of the more... well behaved programs for getting system info.

I have seen MSD show an 8088 system as having 64 MB of extended RAM. It also frequently shows game ports which don't exist, and incorrect information about serial port UART types (the dedicated program called "TESTUART" is much more accurate). And it doesn't properly identify non-Microsoft versions of DOS; it shows IBM PC DOS as being "MS-DOS".

But the one cool feature that MSD has is the Memory Browser, which lets you look at the copyright messages and other text contained within the ROM of the motherboard, video card, and other adapter ROMs.

Cimonvg
March 23rd, 2014, 12:29 AM
hello .
dont remeber if Dr.Hardware runs on 8088, but it also has a good BIOS scan function
/cimonvg

Ole Juul
March 23rd, 2014, 01:20 AM
I've got Snooper and Amidiag in a file called diag.zip here http://cgs.coalmont.net/. They're both worth having, and are old enough to understand this hardware.

skouris33
March 25th, 2014, 09:39 AM
Thank you all for your replies! I run MSD and it says "ok" for extended memory (no Kb). Then I downloaded Snooper and Amidiag (many thanks to Ole Juul). Amidiag could not load at all, but Snooper loaded and said "no extended memory" (it said "no expanded memory" too). So I'm certain that the previous diagnostic program I used was false

Chuck(G)
March 25th, 2014, 09:58 AM
The quick way of determining presence of extended memory is to put 8800h into AX and issue an INT 15h. If AH comes back with 88H, the function isn't supported and you can safely assume there is none. I suspect that the program cited forgot to make that check and simply assumed that 88h/15h was supported.

Stone
March 25th, 2014, 10:11 AM
The bottom line is you don't need any program to tell you than an 8088 doesn't have any extended memory. :-)