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Rtc module on serial com3 port

Robin4

Veteran Member
Joined
Sep 25, 2011
Messages
501
Hey,

Its very hard to find a good I/O 8bit isa card with a working Real time clock on it..

Lately (a month or so) i had bought a Everex EV-170A I/O card new in box.
I thought it could came with an RTC module on board. But after receiving the item i was a little bit
disapointed. ( yes it has an empty place for an RTC, but dont know which components i need to solder it on this board.) So i looked further and finding an DTK PII-144 penta 5 I/O ISA controller card..
Hoping that one would work. But no.. The biggest problem is that only one COM port does work..
I cant get the LPT port regonized by the system..
And also the RTC onboard on this card doesnt seemed to by regonized by the system or diagnostic tools like ` CHECKIT` So it could by a defective ISA card, or the setting wont be accepted by the system..
This card doesnt using IRQs, only weird onregonized settings you can set.. Tried different things, but no LPT regonizasion by my system..

I love the have a RTC clock on it, because:

My ST JUKO V20 8088 doesnt have one.. And its not really nice to set the time and date when the system gots power uped. And it makes my system more complete when it has a RTC on the system...

BUT finding a good one is just a hell.. So i had an idea in my mind. But iam not familiar with electronics.. So i dont know if it could work..

I know that you can buy little RTC seperate boards...

Its it possible to create a little RTC device / board that could compatible with or the BASIC ROM IC SOCKET

or that is possible to connect it on the onboard COM 3 header on the I/O card...

Why a seperate RTC board?

Because older solutions have problems with the year 2000.. So now it is maybe possible to override it with a seperate new custom RTC module...

Is it possible to make it BASIC IC ROM SOCKET OR SERIAL PORT COM3 compatible??
Can some one with electronics knowledge help me with my idea, and if its possible to make scheme to create a custom RTC board..
 
Why waste a whole port on a clock? Why not just use a no-slot-clock (aka "Phantom Clock Chip"). They're still in production.

Basically it's a DS1315, crystal and battery installed on a small PCB between a socket and header that fits underneath the BIOS ROM chip. Very popular on Apple II systems, but there's no reason it shouldn't work on a PC.
 
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Why waste a whole port on a clock? Why not just use a no-slot-clock (aka "Phantom Clock Chip"). They're still in production.

Basically it's a DS1315, crystal and battery installed on a small PCB between a socket and header that fits underneath the BIOS ROM chip. Very popular on Apple II systems, but there's no reason it shouldn't work on a PC.
The DS1216E works great in my 5155. It should work in the JUKO, although I can't guaranty it. They are still available new from Maxim. In fact, the one that I bought from them has a date code 1007 which I believe is the 7th week of 2010. Maxim sells the part only. I don't think they provide the driver for it, but if you decide to buy one form them, send me a PM and I'll provide the driver and instructions.

Greg
 
Why waste a whole port on a clock? Why not just use a no-slot-clock (aka "Phantom Clock Chip"). They're still in production.

Basically it's a DS1315, crystal and battery installed on a small PCB between a socket and header that fits underneath the BIOS ROM chip. Very popular on Apple II systems, but there's no reason it shouldn't work on a PC.

Can i pay with paypal on that site? And what type i have to choose from, there are more then one.
I dont come from the USA or UK, i live in the netherlands.. And dont have any credit card..
If i buy international i always use paypal.. Because its handy and fast without any hassle.

I dont mentioned that its need to have the calender too.. So i need a RTC / calander solution.
If i could use it between the bios rom chip and IC socket then that would be great!!
 
I don't know the answers to your questions, but the folks at Maxim might--and there probably are other distributors who can obtain the product, as Maxim is the manufacturer. You'd probably want to go with a DS1216E, which would fit a 28 pin EPROM socket. Here's the datasheet (Yes, it also has a calendar, but accuracy is only guaranteed to the year 2100, so in 88 years, you'll have to find another solution).

Some years back, one of the Apple II groups made up a bunch of these for the 24-pin Apple II ROMs as well.
 
Is this the same device:

http://www.brutman.com/PCjr/DS1216E.html

Only one IC chip??
Yup, one chip in a special pass-through socket.

FWIW, I think the Juko board (and most, if not all, the clones) uses 28-pin ROMs so you should be OK, but in a PC (or XT?) with 24-pin ROMs you'd need an adapter and a replacement EPROM; I don't think the SmartWatch comes in a 24-pin version.
 
Yes, That's the same thing. But if you zoom in on the date code, it reads 9112, which means that it was made the 12th week of 1991. Now the device is designed so that the battery is not "connected" untill the first time it is powered up. So, if the unit is brand new, as the seller say's, the battery probably isn't dead. But after sitting around for 21 years, I don't think it would have a whole lot of life left in it. That's why I bought mine from Maxim (on Chuck(G)'s recomendation). The one that I bought recently was a replacement for one that I bought in 1985 or 86. So that one's battery lasted 24 or 25 years!
 
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EDIT:

YOU GUYS ARE FREAKIN GOOD!! RTC problem solved i hope.. I ordered it on ebay.. (was much easier then buy it from a foreign company..)

OOPS, I guess I was to slow. I didn't see your last edit untill after I left my previous post. Hopefully you have at least a few years of battery life in that one.
 
Maybe more than a few yeaars, from Maxim AN505:

In addition, many of the Maxim modules incorporate a "Sleep Mode" function that isolates the battery until system power is first applied. This feature allows the module products to be assembled and fully tested; the electrical load is then removed from the battery. Thus, the parts can be left in inventory for an extended period without removing any charge from the battery.

And, from the DS1216 datasheet:

Each DS1216 is shipped from Maxim with its lithium energy source disconnected, ensuring full energy
capacity. When VCC is first applied at a level greater than the lithium energy source is enabled for battery-
backup operation.

The biggest danger is that you're not buying a "new" module. But the listing says "new", so if the seller is telling the truth, you're fine.
 
No problem. Ill try that one from ebay out. Few month later i always can buy from maxim..
First want to know if this device is the solution iam looking for.. I only can try it out and hoping is the right solution..
 
I received the RTC unit.. I want to try it out..

Software Installation
Here is the link to DS1216E.ZIP.

Boot the machine to DOS and run the TESTCLK.EXE program. This will ensure that the DS 1216E can be found and programmed.

Next, use the DOS software to set the current date and time on the DS 1216E chip, and add the software to your AUTOEXEC.BAT file. The program is called CLOCK.COM, and it does not stay resident in memory.

If you change the date and time using the DOS DATE and TIME commands, it will *not* update the DS1216E - you need to use CLOCK.COM to update the DS 1216E. However, you should not have to do this often.

An alternative design for the software would have been a device driver that stays resident and integrates with the DOS DATE and TIME commands. I generally don't like that approach, as you rarely want to set the date and time - you are more interested in reading it at bootup.

It says i need to use TESTCLOCK.COM the see if it could work and been programmed..

But

Next, use the DOS software to set the current date and time on the DS 1216E chip, and add the software to your AUTOEXEC.BAT file. The program is called CLOCK.COM, and it does not stay resident in memory.

How do i setup it in the autoexec.bat?? What line do i need to add to autoexec.bat..?
 
Easy.

I don't know where on your hard drive you copied CLOCK.COM, but let's say you put it in C:\MYCLOCK

You simply add a line (using EDIT or whatever text editor you have handy) to AUTOEXEC.BAT that says:

C:\MYCLOCK\CLOCK

That's it!
 
I have runned TESTCLK.com and it seems to working..

But i dont have the CLOCK.COM program that mentioned here. Because iam using Compaq MS-DOS 3.31 REV G and it seems it doesnt have clock.com in it.. Maybe on the installation diskettes, but not in the C:\DOS directory.. Its only have clock.sys file / program..

And i dont have EDIT.COM in COMPAQ DOS 3.31.. So i dont know how the edit does..
 
The clock.exe (not .com) is in the zip file on the webpage linked above - http://www.brutman.com/PCjr/DS1216E.html.

You will need a way to copy this file from a modern machine to your vintage one.

Instead of Edit, you would edit the autoexec with the Edlin program. It is not intuitive, and if you can it might be easier to edit the file on your modern machine (assuming once again, that you can copy back and forth).
 
Instead of Edit, you would edit the autoexec with the Edlin program. It is not intuitive, and if you can it might be easier to edit the file on your modern machine (assuming once again, that you can copy back and forth).

Alternatively, you might try:

ECHO C:\MYCLOCK\CLOCK >>AUTOEXEC.BAT

Which would append the line to the end of the AUTOEXEC.BAT file.
 
i can confirm that the RTC working great..

I red the included manual, the guy has wroten it. But he mentioned it that that clock file have a name that is called clock.com
But there isnt a clock.com file. So thats made me confused a little bit, what file to use to program the clock..
It is indeed the clock.exe file..

Its programmed if you use:

mm/dd/yy for the date HH:MM:SS for the time and you also can set the day: MO, TU, WE, TH, FR, SA, SU..

It can be configured seperaly.. (the year is optional, and not needed to set if it was set good)

I only think, diagnostic programs cant detect this RTC clock upgrade. But need to test that.. Now iam going to check EDLIN program would work..

Isnt there any norton utility that could edit autoexec.bat and config.sys, because i dont like to swap the files from computer to computer.. I only want to edit it on the same NEC V20 computer.. that is more easier for me..
 
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