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Has anyone ever heard of this RTC module before?

VERAULT

VERAULT

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So I was testing and repairing a blown Tantalum Capacitor on an Apple II card so I pulled out my IIe platinum to test it out in. I had forgotten this computer came with an RTC module under the CF Rom. Figured I'd take some pics and investigate a bit.
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Its labeled ClockPro 4000-90. Has anyone heard of it? Its got a Dallas DS1216 chip in it. The bottom portion is epoxy blobbed. It has 4 solder pads on the top. Think I can solder a CR2032 external battery holder to it and use it?
 

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The Dallas chip was very popular in the earlier days of computing. Unfortunately the battery is not replaceable. While the official version is no longer produced I think there are some alternatives. Though replacing the module isn't likely what you're looking to do. There are Internet tutorials on how to replace the battery in the Dallas chip, if you're looking to revive it you might want to look them up.
 
The "no-slot clock". Although the chip inside is labeled DS1216; in fact, it's a DS1215 with the crystal and battery added. I wonder if anyone is still making them, as the 1215 is still available (even in TSOP). The battery connects to pins 4 and 14 (see Datasheet. You can connect an external battery, but you'll have to break the connection between either pin 4 or 14 on the small DIP from the PCB. Very similar to what's done refurbing the Dallas chip in many PCs.
 
Chuck(G) said:
as the 1215 is still available (even in TSOP)
Click to expand...

I think the DS1215 is technically discontinued but they still make the DS1315, which is completely interchangeable. (I have a tube of new DS1315s and some recycled DS12xxs I got from Aliexpress and they both work in my homebrew boards; I put "xx" there because the ones I have are also labeled "DS1216", which I suppose strongly implies they were salvaged from modules like this.)

As Chuck says, the battery is going to be connected to either/both of pins 4/14. The design allows using two batteries for belt-and-suspenders protection, the circuitry inside uses whichever input has higher voltage. If there's only one battery the other input is supposed to be connected to ground, but if that's not an "official" Dallas module they might not have done it right.
 
well this isnt the typical dallas modules I have seen that are a black box module that you carve into the top to get access to the batteries. This has a socket and the dallas chip on top so I wouldnt even know where to cut into it.
 
Take a look at the photo you posted. The 16-pin DIP pins are quite accessible from the top; in contrast to the usual DS1287 blocks that completely bury the DS1285 chip inside.
 
No, this is an honest clock, running from a 32768 Hz crystal. So it's as good as the crystal's accuracy.

My microwave oven's clock runs fast to the extent of several minutes per month, while my oven's clock, which uses the traditional synchronous motor and gears is rarely off by more than a few seconds. At the same time, a cheap Chinese clock with plastic gears sitting on my bookcase is pretty much bang on, so long as the single AA battery is replaced when depleted.
 
Looks like someone is make something similar:

www.reactivemicro.com

No-Slot Clock

The No-Slot Clock v1.0 allows your Apple II to remember the date and time. It will work on an Apple II, Apple II+, Apple IIe, Apple IIc, and Clone systems. It features dual battery holders. Two CR
www.reactivemicro.com www.reactivemicro.com
 
Chuck(G) said:
No, this is an honest clock, running from a 32768 Hz crystal. So it's as good as the crystal's accuracy.
Click to expand...

I guess I need to buy better crystals next time because, yeah, the DS1215 in my "daily driver" also drifts around three minutes a month. Which considering the criticality of the system is, well, perfectly fine. (To correct for the drift the lazy way I set up my mTCP dhcp script so it runs NTP and syncs up the clock whenever I use networking.)

VERAULT said:
well this isnt the typical dallas modules I have seen that are a black box module that you carve into the top to get access to the batteries. This has a socket and the dallas chip on top so I wouldnt even know where to cut into it.
Click to expand...

Here's a datasheet for an "official" DS1216 clock module in form factor of the one you have, IE, the clock embedded in a pass-through sandwich with a ROM socket on top. I don't know if yours is an actual Dallas-manufactured module that just has a house-brand sticker on it or if it was manufactured independently, but they all function identically. (And were sold under a lot of names, like "Smartwatch", ROM-CLOCK, "Zero-Slot Clock", etc.) One modern recreation was already pointed out, here's another modern clone.

Since you can see the clock chip from the top in theory at least one way to attack this would simply be to try to snip the pin(s) you need to through the tight little hole in the top as far away from the chip body as possible and solder a wire to the stump. I would suggest doing continuity tests between both pin 4 and pin 14 and pin 8 (GND) on the chip to see if either one is connected directly to ground; if one is you don't need to snip that pin, while if both are that suggests it has dual batteries. The rest of the needed work should be pretty straightforward.
 
Thanks. That doesnt seem to bad. I will give it a shot. On another note. Does anyone know what software/disk image I need to set the date and time?
 
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