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Any way to bypass a password login in CompuPro Concurrent DOS?

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jmetal88

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Derby, KS
With an interest sparked by a free box of 8" floppies, I've wound up purchasing a CompuPro 816/10 system (actually a desktop variant that seems to be called the MP4). After some minor servicing of the power supply and some experimentation with baud rate, I've discovered that the machine actually boots off its original MFM hard drive! I'm kind of curious to see what's on the hard drive, but the boot-up is password protected. Are there any known methods of bypassing the login on one of these Concurrent DOS machines? I have to ask because I had a similar situation with an HP-UX workstation I picked up and found out after reformatting the hard drive that I didn't actually have to because there was essentially an administrative "back door" that could be accessed without a password.

If there's no way around the CDOS login, I suppose I'll just reformat and reinstall after I get the supplies I need to hook up my 8" disk drive, but I thought I'd ask first this time.
 
jmetal88 said:
With an interest sparked by a free box of 8" floppies, I've wound up purchasing a CompuPro 816/10 system (actually a desktop variant that seems to be called the MP4). After some minor servicing of the power supply and some experimentation with baud rate, I've discovered that the machine actually boots off its original MFM hard drive! I'm kind of curious to see what's on the hard drive, but the boot-up is password protected. Are there any known methods of bypassing the login on one of these Concurrent DOS machines? I have to ask because I had a similar situation with an HP-UX workstation I picked up and found out after reformatting the hard drive that I didn't actually have to because there was essentially an administrative "back door" that could be accessed without a password.

If there's no way around the CDOS login, I suppose I'll just reformat and reinstall after I get the supplies I need to hook up my 8" disk drive, but I thought I'd ask first this time.
Click to expand...

A few questions. Does it ask for the password during BIOS P.O.S.T. or is the installed software wanting the password? If the former, you might try resetting the BIOS or just disconnecting the motherboard battery for a minute or so and see if that lets you in.

Late edit: Another thing comes to mind. While in the actual boot process, try to get in the the BIOS by the DEL or F2 key, then search around in the BIOS settings for a "Password" option. This is a stretch but worth a look.
 
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Agent Orange said:
A few questions. Does it ask for the password during BIOS P.O.S.T. or is the installed software wanting the password? If the former, you might try resetting the BIOS or just disconnecting the motherboard battery for a minute or so and see if that lets you in.

Late edit: Another thing comes to mind. While in the actual boot process, try to get in the the BIOS by the DEL or key, then search around in the BIOS settings for a "Password" option. This is a stretch but worth a look.
Click to expand...

It's the OS asking for the password, not the BIOS.
 
I think you're in for a bumpy ride on that one. Can you identify the protected software?
 
I guess I'll see if I can access the drive without logging in after I get the floppy booting. The 8" drives are external on this machine and I'm waiting on some supplies to be able to hook one up.

It does have an internal 5.25" floppy, though. I guess I could see if I could find some CDOS images in the 5.25" format.
 
On a CompuPro CDOS system, the login password is stored in a file called PASSWD on the boot drive - in this case, the hard drive.

Unfortunately there is no "back door". The only way to get around this requires your system have already been configured to permit booting from a floppy, and a floppy disk with a bootable copy of CDOS that has been configured to recognize the specific type of hard drive installed in your system. This will allow you to access the hard drive, and you can then delete the PASSWD file.

You likely know this already, but the CompuPro 816/10 is one of CompuPro's later models not based around the S100 bus. It runs Concurrent DOS 8-16 and will allow you to run some early MSDOS software, but it is not a PC-compatible (ie no PC-style BIOS). If the one you own is the one that was listed on eBay a few weeks ago, it has an internal DSQD 720K floppy drive that requires a CompuPro-formatted boot disk specific to this system.
 
jmetal88 said:
I guess I'll see if I can access the drive without logging in after I get the floppy booting. The 8" drives are external on this machine and I'm waiting on some supplies to be able to hook one up.

It does have an internal 5.25" floppy, though. I guess I could see if I could find some CDOS images in the 5.25" format.
Click to expand...

Over my head on this one. There are some members here that play with this. I've never been much of a CP/M type although I did work with it to some degree back in the '80's. Good luck.

If starting from scratch, here's a few links:

https://en.wikipedia.org/wiki/Multiuser_DOS
http://www.retroarchive.org/docs/CDOS_Installation_guide.pdf
 
hmb said:
On a CompuPro CDOS system, the login password is stored in a file called PASSWD on the boot drive - in this case, the hard drive.

Unfortunately there is no "back door". The only way to get around this requires your system have already been configured to permit booting from a floppy, and a floppy disk with a bootable copy of CDOS that has been configured to recognize the specific type of hard drive installed in your system. This will allow you to access the hard drive, and you can then delete the PASSWD file.

You likely know this already, but the CompuPro 816/10 is one of CompuPro's later models not based around the S100 bus. It runs Concurrent DOS 8-16 and will allow you to run some early MSDOS software, but it is not a PC-compatible (ie no PC-style BIOS). If the one you own is the one that was listed on eBay a few weeks ago, it has an internal DSQD 720K floppy drive that requires a CompuPro-formatted boot disk specific to this system.
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It was listed on eBay -- The drive that's in there seems to be a double-density though? It's a Mitsubishi M4853./

EDIT: Well, the documentation says it's a double-density but it seems to be listing quad-density capacities. Weird.
 
Actually, I have an MFM controller for PC... Any chance I might be able to use that to get into the drive and delete the PASSWD file?

EDIT: The system does try to boot from the floppy if it can't read the hard disk. But I guess I don't know whether I can set it up to boot off the 8", which is the CDOS 816 disk format I have.

EDIT 2: It will try to boot from whatever drive is set to DS0. Whenever the rest of my parts come in I'll wire up the 8" drive, set it to DS0, and see if it picks it up.

EDIT 3: I actually have a couple of the Teac HD floppy drives that can be jumpered to 300 RPM -- apparently that is a valid method for reading/writing quad density disks on PC. I found some quad density disk images for the 816/10+ in Teledisk format that I might try to see if I can get going as another option.
 
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jmetal88 said:
I guess I'll see if I can access the drive without logging in after I get the floppy booting. The 8" drives are external on this machine and I'm waiting on some supplies to be able to hook one up.

It does have an internal 5.25" floppy, though. I guess I could see if I could find some CDOS images in the 5.25" format.
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You need CDOS with a XIOS customized to run on your CompuPro 10+ hardware and its 40MB MFM hard drive - and if you had the appropriate Compupro 10+ boot disk, you could boot from the 5.25" internal floppy. Unless configured to do so, it is unlikely your 10+ will boot from an external 8" drive. I think only CompuPro CDOS v3 disk images exist on the internet and these images (a) were distributions intended for use with CompuPro's S100 bus systems and (b) will not allow you to access your 10+ system's hard drive formatted to work with CDOS v5.
 
jmetal88 said:
Actually, I have an MFM controller for PC... Any chance I might be able to use that to get into the drive and delete the PASSWD file?
Click to expand...

Not possible. For a start, the low-level hard drive format used by CompuPro was proprietary to CompuPro.
 
hmb said:
You need CDOS with a XIOS customized to run on your CompuPro 10+ hardware and its 40MB MFM hard drive - and if you had the appropriate Compupro 10+ boot disk, you could boot from the 5.25" internal floppy. Unless configured to do so, it is unlikely your 10+ will boot from an external 8" drive. I think only CompuPro CDOS v3 disk images exist on the internet and these images (a) were distributions intended for use with CompuPro's S100 bus systems and (b) will not allow you to access your 10+ system's hard drive formatted to work with CDOS v5.
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Well, I did find a couple of images that are specific to the 10+. It's just that they are CCPM instead of CDOS. I am not sure what version they are, but I did notice that my hard drive seems to load CCPM ahead of CDOS so I thought it would be worth a shot.

My 8" CDOS disks are version 4.1E, by the way. Older than what's on the computer, obviously, but newer than what's out on the Internet.
 
jmetal88 said:
Well, I did find a couple of images that are specific to the 10+. It's just that they are CCPM instead of CDOS. I am not sure what version they are, but I did notice that my hard drive seems to load CCPM ahead of CDOS so I thought it would be worth a shot.

My 8" CDOS disks are version 4.1E, by the way. Older than what's on the computer, obviously, but newer than what's out on the Internet.
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If your system will boot off an external 8" drive, and you have the full set of 8" CDOS 4.1 master disks, you will likely be able to access the hard drive by choosing the SYS file designed for use with a 40MB hard drive.

If your 5.25" floppy disk images are CompuPro CCPM 8-16 version 4 or newer for the model 10+, it would likely also work.
 
hmb said:
If your system will boot off an external 8" drive, and you have the full set of 8" CDOS 4.1 master disks, you will likely be able to access the hard drive by choosing the SYS file designed for use with a 40MB hard drive.

If your 5.25" floppy disk images are CompuPro CCPM 8-16 version 4 or newer for the model 10+, it would likely also work.
Click to expand...

Okay, that makes me happy to hear. :)

Yes, I have the full set of 4.1 disks, all four master disks and various support disks as well. My 8" drive parts should be here today, so I'll see if I can get that hooked up and going first, I guess.
 
jmetal88 said:
Okay, that makes me happy to hear. :)

Yes, I have the full set of 4.1 disks, all four master disks and various support disks as well. My 8" drive parts should be here today, so I'll see if I can get that hooked up and going first, I guess.
Click to expand...

I think it's a no-go trying to get it to boot off the 8" drive, so I guess my next step will be to try the disk images.

As far as I can tell (I've been poking around with my multi-meter and oscilloscope) the 8" drive and the controller are both functioning properly, but the controller is refusing to load the heads or actuate the stepper on the drive. My best guess based on the signals I'm seeing is that the controller is configured for a 5.25" drive and is not seeing the index pulses from the 8" drive at the interval it's expecting, so it's not even trying to read anything. (I say this because it looks as if both drives are configured to gate off the index pulse via the drive select line, and the controller is pulsing the drive select line rather than keeping it steady. The pulses happen to line up with all the index pulses on the 5.25" drive, but they are only lining up with a few of the index pulses on the 8" drive -- probably due to the 300 vs 360 RPM difference.)

So I'll see if I can get the 5.25" drive booting, and if I can, I'll see if there's any way to configure it to boot off the 8" once I'm in the system.
 
The lack of available documentation for CompuPro's 10+ systems makes it difficult to know what is going on. While there is a wealth of information available for CompuPro's S100 based systems, likely it is of little relevance to the hardware design of the 10+. CompuPro designed their S100 systems so they could be configured (by means of a switch selection on the floppy controller board) to boot from just the hard drive, a 5.25" floppy and a hard drive, or an 8" or 5.25" or hard drive . Since an external 8" drive was an option that was likely used by few owners of the 10+, my guess is that CompuPro designed the 10+ to boot only from either the built in 5.25" floppy or hard drive.

The CompuPro 10+ being a "closed system", you won't be able to do much with this box if you can't find a floppy boot disk for it. Hopefully the ones you have will work, or someone who has a functional 10+ system can provide one for you.
 
So far the 5.25" drive is just loading the head repeatedly. I think that means that it can't read the disk I wrote? I may have to move the QD drive over to my PC to try and write the disk image.

I've been messing with the drive configuration some and somehow got the 8" drive to activate when set to DS2 instead of DS1. It still will not try to boot off it, but the computer is acting like it's "seeing" the drive now.
 
jmetal88 said:
So far the 5.25" drive is just loading the head repeatedly. I think that means that it can't read the disk I wrote? I may have to move the QD drive over to my PC to try and write the disk image.
Click to expand...

If the drive is repeatedly loading the drive then yes - it is unable to read the disk.

In my experience the M4853 will not read a 5.25" HD disk that has been formatted on an HD drive at 96 TPI DD. Just use standard 5.25" DSDD floppy media. Even better if your PC and image creation software can be made to work with a DSQD drive like the M4853, to allow you to write the image using the same drive you will be using to read the disk.
 
Alright, after changing a jumper on the controller, it does try to boot off the 5.25" disk. Still acts like it has trouble reading it as it only works sometimes and when it does it won't finish the boot (I am using the QD drive on my PC to write the disk). It does show that it starts the floppy loader, but then freezes.
 
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