Real time clock ?

[Mark Smith]

Hi there,

I'd like to get a RTC into my C128 somehow, anyone know of a hardware hack that allows one to be installed (and adjusted from the C= side ? ... some I've seen have to be set on a PC then plugged in) .. something that goes in a ROM socket or as a cartridge would be nice :-)

Or how about something where a clock is added to a 1541/1571/1581 drive ?

Thanks!

Mark

[airship]

Just read this week about some guy who had hacked one into a joystick port dongle, with pass-thru. Can't remember where. If I think of it, I'll post back here.

Jason-Ranheim made a clock/8K battery-backed RAM cart that sold for $50.  Nice little device. Had support in ROM. C64-only though, I think.

Seems to me like there might have been one or two others. Pretty rare beasts, though, even back in the day.

[11001010]

If you use 64HDD, like I do, you can easily access the PC's RTC for time and date from the C= computer.  All the little menu programs and things I write now have the time and date somewhere on the screen.

[arnsfelt]

Here : http://members.elysium.pl/ytm/html/rtcds12c887.html

[BigDumbDinosaur]

Another way is to install a Dallas 1216E smartwatch into the 128's normally empty function ROM socket.  It will be transparent until your custom written machine code wakes it up.  

The original design was worked out by Lloyd Sponenburgh (Lt. Kernal hardware engineer) some 20 years ago.

[Mark Smith]

What a cool solution! :-)

Let me just see if I've got my head around how it works ....

So one of these can go into any ROM socket and then has a real ROM installed on top of it, then it just lurks underneath waiting for the correct sequence of reads to a particular address, once it has a match it hides the real ROM and you either read the time or do another sequence of reads to set the time ... I get that right ?

Mark

[smf]

What a cool solution! :-)

Let me just see if I've got my head around how it works ....

So one of these can go into any ROM socket and then has a real ROM installed on top of it, then it just lurks underneath waiting for the correct sequence of reads to a particular address, once it has a match it hides the real ROM and you either read the time or do another sequence of reads to set the time ... I get that right ?

Mark

http://www.maxim-ic.com/appnotes.cfm/appnote_number/52

[airship]

Maxim still sells them for $26.23/ea. in 1-24 piece quantities.

I wonder if you could work a time reading and writing routine into the corners of a home-burnt C128 Kernal ROM? Maybe wedge it into TI and TI$, too?

[BigDumbDinosaur]

What a cool solution! :-)

Let me just see if I've got my head around how it works ....

So one of these can go into any ROM socket and then has a real ROM installed on top of it, then it just lurks underneath waiting for the correct sequence of reads to a particular address, once it has a match it hides the real ROM and you either read the time or do another sequence of reads to set the time ... I get that right ?

Mark

That's basically it.  A specific sequence of write operations on one location causes the smartwatch to react to the toggling of R/W, chip select, etc., and when the correct series of writes has been executed within a specified amount of time, the smartwatch connects itself and you can read and write it.  If the access mumbo-jumbo isn't correct the activity is referred to the ROM in the smartwatch socket.  I don't recall all the details, since it's been a number of years since I looked at it.  But the documentation should be readily available.

[BigDumbDinosaur]

Maxim still sells them for $26.23/ea. in 1-24 piece quantities.

I wonder if you could work a time reading and writing routine into the corners of a home-burnt C128 Kernal ROM? Maybe wedge it into TI and TI$, too?

Dunno why not.  Rip out the tape routines and usurp their space.  About all the cassette drive was good for was giving the cat someplace warm to sleep.  :skratta:

[airship]

Obviously you haven't read my post about how incredibly cool the cassette port is!

[BigDumbDinosaur]

Obviously you haven't read my post about how incredibly cool the cassette port is!

Oh!  You mean that obstruction on the back of the computer?  It's as useless as the teats on a boar hog.

[Blacklord]

Obviously you haven't read my post about how incredibly cool the cassette port is!

Oh!  You mean that obstruction on the back of the computer?  It's as useless as the teats on a boar hog.

Not that useless, up until late in the 80's 1541's were very expensive in Australia & for quite a while software on tape outnumbered disk based software by quite a large proportion. Until the release of the 64C when the price of the drive fell, not all that many people here had one. As a result, there's still a lot of tape based software around. I have way more cassettes than I do disks - in general I've had verey few failed tapes as well, can't say the same about disks!

cheers,

Lance

[Andrew Wiskow]

Not that useless, up until late in the 80's 1541's were very expensive in Australia & for quite a while software on tape outnumbered disk based software by quite a large proportion. Until the release of the 64C when the price of the drive fell, not all that many people here had one. As a result, there's still a lot of tape based software around. I have way more cassettes than I do disks - in general I've had verey few failed tapes as well, can't say the same about disks!

The situation was quite the opposite in the U.S. and Canada.  I didn't know anyone who had a tape drive when I was a kid with my first C64.  In fact, it wasn't until last year that I first used a tape drive on a Commodore!  And it was also last year that I purchased my first program on tape (Stranded by Cronosoft). 

-Andrew