How do I disable cache memory in DOS?

[SpectraBob]

Motorola is recommending that cache memory in DOS be disabled when using RSS.

What are the step-by-steps to be taken to access that area and then to do so?

Thanks!

[Bill_G]

It is done in the bios .... if available on that computer. Some don't let you do it. Toshiba sometimes had a utility with cache enable/disable as one of the options.

[SpectraBob]

I have both a Toshiba and a Gateway (oldies but goodies)... how do I then get to the BIOS, to view the settings and/or change it to disable the cache?

[KI4RGV]

Google a free program called "CPUcache.com". I keep my RSS on floppies. Before I toss them in my A drive, I put in my CPUcache floppy and deactivate the cache. It's free, simple, and works.

Good luck.

Peter.

[Bill_G]

You get a tiny window of opportunity to access the bios during boot up. The instructions will flash on the screen and then disappear about 2 seconds later. Usually it is PRESS F2 FOR SETUP.

[SpectraBob]

I've seen that on my newer machines, but when I tried hitting F2 almost continuously during boot-up on this Windows-95 machine, it ignored me and simply came up in Windows. Perhaps that's not an option with Win-95?

[Bill_G]

Shouldn't have anything to do with Win95. It is built in by the OEM. Every computer I've ever owned had some kind of setup notice within a few seconds of power on that disappeared quickly, and then progressed with booting to whatever os you have installed whether it is dos, windows, etc.

[SpectraBob]

I know it's hard to believe, but that doesn't come up when I boot her up; even pressing F2 as it boots is ignored and does nothing.

Is there a way to reach Setup thru a DOS command, perhaps?

[Bill_G]

No. Not unless the OEM included it as a utility executable. That's pretty unusual to not have some kind of setup screen available upon power up.

Going back to your original question, are you having problems running an older rss and hoping to address it by turning off cache, or are you just being proactive and following Moto's advise?

[SpectraBob]

Both, actually... I can easily read a Saber II and change its programming, but then cannot write back to the radio. Getting an I/O Error message. Seems others have had this same problem; all my research here on the forum has failed to come up with anything I haven't already tried... other than Moto recommending that the cache be disabled as part of setting-up a laptop for RSS use...

[escomm]

F2 for BIOS? I have always found it to be the delete key...

[Bill_G]

I fired up a Toshiba 105CS and it did not have an initial setup notice. It went straight to autoexec and booted. However, this Toshiba has a utility tsetup.exe in the dos directory. tsetup has all the things you usually see in a bios screen including enabling cpu cache. An old Packard Bell in the shop doesn't have a power up bios notice either. Goes straight to autoexec though I know it has a setup screen warning if the battery goes bad. Then you get no choice but to go through every item. I've had plenty of practice with it. Otherwise, apparently no way to get to the bios if it passes POST. An old Halikan with American Megatrends bios does show PRESS (DEL) FOR SETUP after the memory test, and it has no cpu cache setting. And an old eMachine I have shows PRESS F2. So, it all depends on the machine where the bios setup screen is, and there is no guarantee it will let you set the cpu cache on/off. oy vey.

[wavetar]

You can view a page with a listing of how to get into the BIOS of most major manufacturers here:

http://michaelstevenstech.com/bios_manufacturer.htm

The "esc" key seems to be the one to use for most Toshiba machines. Gateway seems to be either F1 or F2.

[alex]

A trick that also will work is turn the machine on, and keep hitting random keys on the keyboard.

Usually, this will generate a keyboard error at which point you can hit continue, or another key for setup.

-Alex

[Jim202]

I found a small dos program called "cacheoff.com" that works well. Boot into DOS first
and then start the cacheoff.com program. Then go to the other software your trying
to run.

I found the program and downloaded it from a simple search on the web.

If your stuck with a fast computer. there is a moslo.com pro version that you can have
and download for about $29.00 and does the trick. Have been able to play with a
Syntor X9000 low band radio with my 1.8 GHz laptop. I have run out of slow computers,
so started looking for alternatives. It works. Have done Spectra mobiles also with this.

Jim

[SpectraBob]

Thank you, everybody, for all of your information; I'll check into each of them as time allows...

[motorola_otaku]

I found this article on creating your own cache disabling and enabling programs.

http://www.rigacci.org/docs/biblio/onli ... cheoff.htm

Some BIOSes will allow the internal CPU cache to be enabled or disabled. Most modern BIOSes, including Phoenix 4.xx, will automatically enable the internal CPU cache and there is not normally an option in CMOS setup to disable it as there is normally no need to do so. There may be some older DOS programs that need the cache disabled. This DEBUG script will create a program to disable the internal CPU cache and a program to enable it.

Here is a complete debug session transcript to create CACHEON.COM and CACHEOFF.COM. The dashes and colons are prompts that DEBUG uses, and aren't part of what to type in. These programs are not BIOS specific, so they should work with any system with a 486 processor. The only caveat is that certain programs may re-enable the 486 cache; the main group of programs that are likely to do this is programs that use a DOS extender.


C:\>DEBUG

- e 100 0f 09 0f 20 c0 66 25 ff ff ff 9f 0f 22 c0 b8 4c 00 cd 21

- r cx

CX 0000 (output from debug)

:13 (type 13 at colon prompt)

- n cacheon.com (names program)

- w (writes program to disk)

Writing 00013 bytes (output from debug)

- e 106 0d 00 00 00 60

- n cacheoff.com (names program)

- w (writes program to disk)

Writing 00013 bytes (output from debug)

- q (quits to DOS prompt)

CACHEON.COM and CACHEOFF.COM should now be present in the current directory. After turning cache off with CACHEOFF.COM, it should automatically be re-enabled when system is powered off and back on or it can be re-enabled with CACHEON.COM.

You can run DEBUG from the command prompt or in "Run" in Windows. The files get written to whatever your default "My Documents" folder location is. After that, you can copy them over to your RSS machine via floppy or whatever.

[PETNRDX]

I know this is an old thread, but I thot it was worth dredging it up again.
I have been having trouble with a 486-DX 75 that I need to use as a backup DOS machine for running dozens of old RSS programs.
Up til now I just "stored" the programs on this thing because MOST of the RSS programs gave a runtime error or divide by 0 error.
So, I wrote the DEBUG scripts above, and it worked like a charm.
Now all the spooky RSS versions that crapped out work just fine.