Atari Falcon NVRAM House of Horrors - How to Replace Your Real-Time Clock Without the Gore!

Atari NVRAM RTC Real Time Clock Article CoverAs the owner of a vintage Atari 16-bit or 32-bit computer, there are dozens of possible repair jobs you will face one day.  While some of these jobs are straightforward and easy, others are complicated and tricky.  In the case of the Atari Falcon's NVRAM (Non Volatile Memory) chip, which also combines a real-time clock (RTC) and battery, most documented repairs have involved some pretty horrific botch jobs. My hope is that you've reached this page before you've committed this dastardly deed.  If not, welcome to the NVRAM House of Horrors! Mha-ha-ha-haaa!

When your Atari Falcon starts developing amnesia by forgetting it's time, native language, keyboard layout, screen resolution, or other bios settings then your NVRAM battery is dead and needs replacing. Chances are you've heard the rumors that there isn't enough room under the Falcon's metal RF shield to install the Dallas 12887 / 12887A replacement chip with an IC socket.  As a result, many Falcon owners have concocted all kinds of contraptions and altercations to bring the original NVRAM battery back to life.  These hack jobs are documented all over the internet (see examples below).

When I faced changing all three of my Falcon's NVRAM chips, I desperately wanted to use IC sockets to make future replacements quick and easy. One of the solutions was to cut a holes in the RF shields to make room for the new chips and sockets. I refused to do do this. However, if I didn't use IC sockets, I would have to desolder and resolder new chips every 5 to 10 years.  I resented this alternative too as it involved too much heat stress and risk to the electronic traces. Taping batteries and soldering jumper cables to boost the dead chip was also out of the question.

Granted, there are two schools of thought on this subject. The first is that some folks don't care about what the end result looks like; all that matters to them is that it works. Others believe that the original state and aesthetics of the computer should not be altered as it depreciates its value. It is my belief that in 2010, these rare computers should be treated like vintage sports cars - you wouldn't hack the insides of your 1991 Lamborghini to fit a Volkswagen battery, would you? After searching the internet endlessly, I finally found a simple solution. Now there's no excuse for butchering your old clock chip anymore! Luckily, as long as you haven't destroyed your RF shielding, whatever workaround you've done previously, the process is reversible!

Here are some previous "horrific" workarounds found across the Internet that are no longer necessary.

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The Solution

If you wish to perform this mod, do so at your own risk. If you don't know what you're doing, take it to a repair technition.

Alternativly, there's an extensive work around you can implement using KEEPTIME v1.0, ROMSPEED v3.10, and NVRam together.

1. Set half the day aside and don't walk across the carpet in your socks! Ground yourself at all times while touching the Falcon's PCB.  One spark off your finger could fry your Falcon for good! Also, you'll need steady hands for soldering, so lay off the coffee until your done.  Better yet, if you hold off on the coffee altogether, you'll earn yourself a beer afterward as a reward.

2. Unless you have a specialized heat gun that can desolder all 24-pins at once, you're going to have to use a mini hacksaw to cut the chip width-length through the center, top to bottom.  Next, carefully break the plastic chip apart into little pieces with a screwdriver but don't use the motherboard as leverage - there's electronic traces underneath!  Once the chip is off the pins, simply use tweezers and the soldering iron to pull out the pins one by one.  To clear the left over solder from the holes, use a solder sucker on one side while heating the other side with the iron (desoldering braid takes forever and doesn't work well for this).  Now you're ready for the simple solution to fit a removable NVRAM / RTC under the hood without damaging the RF shield.

Atari Falcon NVRAM IC Socket Diagram wtih Dallas 12887 Chip3. Digi-Key sells a special ultra low profile 24-pin IC socket, model# ED5624-ND, that stands a mere 0.95" off the PCB. Using this along with the Maxim Dallas 12887, 12887+, or 12887A RTC will give you more than enough room to fit everything underneath the RF shield. By the way, all models function the same; the A version has a special RAM clear function but it doesn't appear as if the Atari uses this feature.  Once you've soldered the IC socket, pop the new chip on top! That's it!

4. You're almost ready for that beer!  Finally, you need to initialize the new chip with resetnvr.prg. Put this utility in an empty "AUTO" folder on a floppy before starting the Falcon for the first time. Alternatively, you can try resetting it manually by pressing the following key combination upon booting (but you need to be fast): left ALT + CONTROL + right SHIFT + UNDO.  Next, use bootc123 by Dr. Uwe Seimet to configure your new Dallas 12887 real-time clock and system settings.  There's a few other configuration utilities available, including the config.prg file on your factory system disks, but there but none of them are as detailed as this.

Atari and Beer5. That's it! No more gore! No more horror show!  Now, and for the rest of your Falcon's natural life, you can easily replace your NVRAM in a matter of minutes by popping it in and out of the IC socket! Congratulations! Go get yourself that beer!  Now that you know this, you have a moral obligation to prevent others from butchering their Falcons! Go and spread the word!