Getting a DTK Peer-2030 computer running

[Bill-kun]

My resurrection (mis)adventures continue. This time it is a DTK model Peer-2030 that I got secondhand locally about a year and a half ago. Some info on it:

• No integrated video card
• No integrated sound card
• Has a 5.25-inch floppy drive as drive A
• Has a 3.5-inch floppy drive as drive B
• Takes a 3.5-inch IDE HDD, since it has a specific bracket/cage for it

The symptoms are:

• Power supply powers on okay
• Gives a single beep at power-up. The kind of single beep that is supposed to tell you everything is normal.
• Keyboard lights light during POST
• Floppy drive lights light in sequence during POST, but they do not do a motor test
• Computer seems to reboot itself immediately after the floppy drives light up. When the floppy drives light up in sequence again, it resets itself again.
• Turbo button is functional (the floppy drives take longer to light up if turbo is off)
• Reset button is functional
• No video output at all

 

[Bill-kun]

Bump. Any help, please?

 

[jafir]

Have you tried another video card?

What model of motherboard is in it?

 

[Plasma]

CMOS battery is likely dead. You will probably need to remove it and add an external battery.

https://www.ultimateretro.net/en/motherboards/1923

 

[Bill-kun]

For reference, I found the computer's manual online. https://www.manualslib.com/manual/301966/Datatech-Enterprises-Apex-386sx-20.html#product-PEER-2030

Have you tried another video card?

What model of motherboard is in it?

I've tried two different 16-bit video cards plugged into a 16-bit slot. The leftmost slot is 8-bit.

I actually can't see any markings on the motherboard saying what the motherboard is. When I get it out of the case, I can take a picture to see if anyone can see something I'm not. It at least mostly matches the board that Plasma points to:

CMOS battery is likely dead. You will probably need to remove it and add an external battery.

https://www.ultimateretro.net/en/motherboards/1923

Right. My experience is now enough that I should have thought of that myself for a boot problem like this. Fortunately, the motherboard is not too difficult to remove from the case. The CMOS battery is a barrel battery that has leaked a bit onto the motherboard. I will remove that, clean the corrosion, add a new battery, and report back.

According to the manual, W13 is the jumper that selects the battery as internal or external. J7 is the external battery connector.

 

[jafir]

I found a printed manual for a PPM-2030C which seems to be the same board. It doesn’t look like it has any extra information compared to the manual you linked to, but I’ll probably try to scan it later, just so it can be archived somewhere for completeness.

 

[Plasma]

Yes the first thing I do whenever there's weird boot stuff is make sure the CMOS battery is good. If it's dead you can have many strange issues.

The page I linked has various manuals if you click on downloads. You probably also need to set the W12 jumper to color (pins 2-3 closed). Normally you want "none" if using EGA/VGA but I don't see that option.

 

[Bill-kun]

According to the manual, W13 is the jumper that selects the battery as internal or external. J7 is the external battery connector.

I got a new CMOS battery with a 4-pin connector. I installed it and moved the jumper W13 from 2-3 to 1-2 for the external battery. No change. I measured the 4.5 V. battery and it measures 0.35 V. So I have to get another another battery. I had my local computer repair store order some AA battery holders. I'll scavange the connector from this new dead battery.

You probably also need to set the W12 jumper to color (pins 2-3 closed). Normally you want "none" if using EGA/VGA but I don't see that option.

W12 was already set to 2-3. I removed the jumper and there was no change, so I put it back. But if the CMOS battery is the limiting factor at the moment, this point is moot for now.

 

[Bill-kun]

I took out the motherboard and gave it some vinegar to get the battery corrosion off (Varta barrel battery!). The corrosion has destroyed a few traces on the motherboard. Thanks to a recent video by Adrian that shows I can fix this problem by bodging, I am planning on bodging it.

 

[Bill-kun]

Update:

I used continuity mode to see which of the traces had been severed. I found that the yellow wire and the white wire from the power supply connector had both been severed. I bodged them using a suitable wire thickness. I put the motherboard back in and plugged everything into it. It starts booting up! So I'm all the way back to where it was when I first got it a couple years ago.

It says:

FDC error user check !
FDD seek failure !
System memory mismatch, run SETUP
Display card mismatch, run SETUP

It always has given the FDD and FDC errors. I never got to fix them then. Now I am finally in a position to ask for help on how to fix those.
The BIOS says there is 1024 kB. of extended memory and won't let me change that.
The diplay card is one that I got used. This unit came to me without a video card, I think.
Here are pictures of the screen, memory banks, and video card. Please tell me where to start.

 

[Plasma]

Have you put the correct config for your system in the setup?

 

[modem7]

Expanding on what Plasma wrote:

"Display card mismatch"

The card type (CGA, EGA, etc.) in CMOS SETUP does not match the actual card fitted.

"System memory mismatch"

One or more of the RAM amounts in CMOS SETUP do not match what was discovered by the power-on self test.

The screen shot indicates that the POST found 640 KB of 'base' memory, and 1024 KB of extended memory.
If you have no reason to think that that is incorrect, then those are the two figures that you would enter into CMOS SETUP.

If you have a reason to think that that is incorrect, what is that reason?

 

[Bill-kun]

FYI, I don't have an HDD attached yet.

Here are screenshots from the BIOS.

Here are the issues:

1. CMOS battery. The new CR2032 button battery that I have connected to the motherboard does not seem to be providing power to keep the BIOS settings. The battery reads 3.25 V. There is a jumper on the motherboard that controls whether the battery is internal or external. I had it set to internal.

2. Display card mismatch. The BIOS says it is automatically set. So I don't know what it means by that. Unless me going into the BIOS causes it to be sensed. On subsequent boots it doesn't say there is a mismatch.

3. Memory mismatch. Like the display card mismatch, it seems that me going into the BIOS causes the memory to be sensed and then on subsequent boots, the error does not occur. From the diagram of the motherboard linked above by Plasma, memory banks 0, 1, and 3 are unpopulated. Bank 2 is populated with two stick boards. I assume that is qty. 2 of 512 kB. giving the 1024 kB. extended memory. So that seems to match.

4. FDC error user check and FDD seek failure. Even after setting the floppy drives in the BIOS, neither of the floppy drives do seeking, but the light on each lights up. Neither light stays solid. In fact, each of the floppy drives looks and sounds like it's trying to do the seeking. Maybe the drives just need cleaning inside? Would the floppy drive controller error occur because the seeking is not happening properly? Or else, why would the FDC not be functioning, and what checks should I do?

 

[Bill-kun]

CMOS battery is now working. Jumper W13 was set wrong earlier. It is now on pins 1-2.

For each of the floppy drives, I have now blown dust out with compressed air, cleaned the worm gear, cleaned the drive head, and re-greased the worm gear. If the two floppy drives were not definitively seeking before, they certainly sound like they are doing so now. But there is no change in the FDD or FDC errors.

 

[modem7]

CMOS battery is now working. Jumper W13 was set wrong earlier. It is now on pins 1-2.

1-2 = External battery.

A 3 volt battery is not much for the 'external' battery connector, considering that the norm is for there to be two diodes between the external connector and the RTC chip (i.e. reducing the voltage that reaches the RTC chip). I don't think that you should expect the CR2032 to last a long time.

But there is no change in the FDD or FDC errors.

According to the PEER-2030 manual:


The FDC error suggests that the motherboard has some kind of a 'problem' with the floppy controller you are using.
What is the floppy controller you are using?
Tried it in a different slot?
Cleaned the edge connectors on it?

 

[Bill-kun]

The controller card is for both HDD and FDD. I took out the controller card and found that there was corrosion on its edge connector and its 16-bit "home" slot which is slot 8 (that is, 8th from the left as seen from the front of the computer). I dipped the card edge in vinegar for about 20-30 minutes, rinsed it with water, let it air dry, and put it back in. Boot ups after that simply had a blank monitor screen and didn't do anything. I checked the monitor connection and it was fine.

I then ordered Deoxit. I removed the card, sprayed the slot, let it dry, put the card back in, and tried a boot. Same thing. I moved the controller card from slot 8 to slot 5, and stuff now appears on the monitor. The computer only shows the following, and proceeds no further. The floppy drives sound like they are trying to seek, but the seek is not "proper and controlled" if you will.

Conclusion: Slot 8, the home slot for the controller card, still has corrosion preventing contact with the controller card's edge connector. If I want to use it, I will need to more thoroughly clean it.

But the computer is still stuck in the middle of booting up, so that seems to indicate something on the controller card is still wrong. What do I do next?

 

[modem7]

You have a motherboard where a battery has leaked. Perhaps you now have a slot #5 related problem.

 

[Bill-kun]

Also, I did not notice that lowercase accented letter E on the lower left of the boot screen. Maybe that means something.

I will try the other 16-bit slots for the controller card.

 

[modem7]

Also, I did not notice that lowercase accented letter E on the lower left of the boot screen. Maybe that means something.

Coincidentally, I am now sometimes seeing something similar with my IBM CGA card, and I think, "Is that a video RAM chip on its way out?"

 

[Bill-kun]

The letter E does not appear every time. I haven't noticed it appearing again.

I tried the other 16-bit slots but each time the computer has either only gotten as far as pictured above in post #16, or gets just a little bit farther and allows me to go into the BIOS. The improper seeking on the floppy drives still happens. So something appears to be not right on the controller card.