PCEM stopped working correctly

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PCEM stopped working correctly

Post by djwestly »

Had a new configuration set up (V16) and running on windows 7 x64 but it became non-responsive, so I killed the process using task manager.
When I tried to restart that cofig, screen opens but is blank (not even post info is shown) and I hear a high pitched beep followed by a low(er) pitched beep.
The window title bar shows speed of 100%.
The mouse is also captured (and released) as expected.
The menu bar items work as well.

This also affected my other configurations (that were working before this happened) the same way (i.e. blank screen + 2 beeps).

I extracted the archive again, overwriting the existing files hoping this would fix the problem but it didn't.

Anyone else experienced anything like this?
Are logs generated somewhere that I can look at?

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Re: PCEM stopped working correctly

Post by unreal9010 »

Download v17 and try again.
It's pointless to diagnose a past release.
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Re: PCEM stopped working correctly

Post by Arjen42 »

Two beeps means the startup display mode is not set correct in nvram. You will need set this to the correct value Monochrome, Color 40x25, Color 80x25, or EGA/VGA, or Not Installed.

However if your screen is not working you cannot do this, so you first have to fix your screen. Most likely the rom file of the graphics adapter is missing.

If you don't have the correct rom you will have to chang your display card to MDA using the Configuration Manager. First make sure the mda.rom file is located in the roms directory. (mda.rom is the only display card rom supplied with PCem.)

If this works you'll get a little further, you will get text, and likely an error message and two beeps. You still will have to set the correct value in nvram using the setup program located in the BIOS or on floppy disk depending the type of computer you're emulating.

TLDR: This is PCem perfectly emulating a computer, either misconfigured and/or with a broken/missing display adapter.
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Re: PCEM stopped working correctly

Post by ruben_balea »

Try going to the nvr subfolder in the PCem folder and deleting the nvr file with a name resembling your configuration name and emulated machine name, that file stores the motherboard configurations and can get corrupted.
For example if your configuration name is "MS-DOS 6.22" and the machine is a "Dell System 200" the nvr fille will be called "MS-DOS 6.22.dell200.nvr"
After that the machine should start and display some message telling you to press some key to enter the CMOS setup to set the correct settings.

Sometimes the video card can dissapear because PCem loads a default configuration if a rom file was not found, if that was the case selecting again a proper video card would fix the problem.
But remember that 8086/8088 motherboards are not compatible with every VGA and later video cards because some video card BIOS on those cards use 286 instructions, some may even use 386 instructions and won't work on a 286 either.
So if you are emulating an 8086/8088/80286, try choosing the MDA or Hercules video card and see if it works before choosing a newer video card.
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