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Gateway 2000 486 DX/2 50

VERAULT said:
I have a cr2023 running to them but this system WILL NOT retain any of its settings. I have no idea why. The date and time are correct in the photo only because I just updated it.
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VERAULT said:
I put the jumper back in where I originally had it and I can get 3.1V at both VCC pins on the 82c206 powered off. Powered on I get 4.91V from both VCC pins.
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And the PSRSTB# pin too (just to be sure) ?

And measuring 3.1V with a CR2032 in place, presumably you have the J8 jumper in the 3-4.5V setting.

Reading the OPTi 82C206 datasheet, I do not see anything like "3-6V operation" for the Vcc pin.
The best that I can find is in section 5.1, that indicating a maximum rating of +6.7V for the Vcc pin.
Could it be that 3.1V is too low for operation of the OPTi 82C206 ?
Do you have the means to connect up a larger voltage battery ?
 
modem7 said:
And the PSRSTB# pin too (just to be sure) ?
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Ok hold on that one

EDIT::::: 3.12V from pin #7 PSRSTB# with power off.

modem7 said:
And measuring 3.1V with a CR2032 in place, presumably you have the J8 jumper in the 3-4.5V setting. 4.9v with power.
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Yes that is correct.

modem7 said:
Could it be that 3.1V is too low for operation of the OPTi 82C206 ?
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Thats where I am leaning right now.

modem7 said:
Do you have the means to connect up a larger voltage battery ?
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Id really rather now Connect a 9v battery (I may have one measuring 7v which was too low for my multimeter) Im just afraid the current will be too much!
I did order these which should arrive in a couple days: https://www.ebay.com/itm/254628295576
 
VERAULT said:
I'd really rather now Connect a 9v battery (I may have one measuring 7v which was too low for my multimeter) Im just afraid the current will be too much!
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Yeah. You don't know if the '6.4V' setting of J8 is going to reduce the measured-at-7V battery voltage to something below the max. Vcc rating of 6.4V
 
A little something else to mention. I have a small baggie of these laptop RTC battery recplacements. You know, coincell battery in heatshrink with two wires coming out to a tiny connector. Smaller, thinner cell than a cr2032. I figure I might as well use them for something so I took two (still measuring over 3V) and put them in series. When I test the new cells I get 6.2v. When I connect them to this gateway I get 2.5V even if I test at the pins of the battery connection!!! So that wont work. Too old maybe?
 
VERAULT said:
Smaller, thinner cell than a cr2032. I figure I might as well use them for something so I took two (still measuring over 3V) and put them in series. When I test the new cells I get 6.2v. When I connect them to this gateway I get 2.5V even if I test at the pins of the battery connection!!! So that wont work. Too old maybe?
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Some thoughts:
- A poor connection somewhere.
- Bad battery, where it's terminal voltage drops excessively under even a little loading.
- {Unlikely}: Good batteries, but when the J8 jumper is in the 6.4V position, a motherboard fault/mis-design is overloading the batteries.
 
Well the 6v cr2032 batter holders came in. I just made one for my IBM P70 I was also working on and it works fine in that system. Diodes came in today as well. Problem is I am out of CR2032 batteries so I had to order some of those tonite.

So I will post back soon with something to try and tackle this 1992 gateway RTC problem.
 
While waiting for the CR2032 batteries to come in I spent the past two days working on the 1994 gateway 2000. I thought I had a power supply issue as the machine was behaving strangely and locking up. I have been using the lo-tech rom card with XT IDE universal bios to try loading it up and its just not working. I think Im going to use the dip switches on the board and disable the single IDE channel and add a Winbond IDE controller much like I did on my 486 tower.

Im getting really inconsistent results from the onboard IDE, but if I use an XTIDE 8 bit card everything works great.

These two Gateways are kicking my butt.
 
So The batteries came in and I built up another 6v dual cr2032 pack. It came out to 6.5v. I was thinking about the voltage drops I was getting testing before and thought it wasnt necessary to use a diode here as well. I moved the jumper to the 6.4V position and connected the battery up. I measured 4.9V at both VCC pins and the PSRSTB# pin. Same as if power was connected and on. So far its holding the settings so I think we have this problem sorted.

I dont think this explains the different voltage jumper positions at all however. IT only seems to hold the settings above 6V.

On another note I added a rom card with XTIDE universal Bios and this 1992 gateway has no problems with CF card auto-detection from the onboard IDE. Which makes no sense that the 1994 (smaller board) gateway has such an inferior IDE device on the mainboard. Hopefully that IDE controller I bought will resolve that.

Either way I can continue on this 1992 gateway 486 build. That makes two systems down and one to go!
 
I guess I was wrong. I booted up the 1992 486 gateway to test a disk on module that came in the mail and the settings were clear. Makes no sense. The voltage is still good. I dropped the jumper from 6.4v to 6v and added the settings again.
 
So I was able to get my 1gb DOM working on the 1992 onboard IDE with XTIDE universal bios. I tried loading it with my SDLPT device but its acting strangely. I have the motherboard jumper set to LPT Bi-directional. And the strange thing is the blue led for activity on the SDLPT turns on as soon as power is applied to the machine. IF I disconnect the power cable (usb cable) the blue activity light is always on when power is applied. Strange. I set the jumper on the motherboard to output only, same thing. I change the SDLPT driver from SDRIV.sys to SD.sys and move the jumper... same thing. This parallel port is acting strangely.
 
Ok I figured out the parallel port issue on the 1992 gateway 2000 so I can use my SD2LPT...

IMG_20240312_173337.jpg

As you can see LPT1 uses a nonstandard address.

If I change it to LPT2 its normal and works great!
IMG_20240312_173755.jpg
 
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