Support for DS1644 Timekeeper

[Batsch69]

Is it possible to add support for Dallas DS1644 Timekeeper?
This device has 32kb RAM suitable for holding the option-ROM, and a RTC!
I pluged this device as a 28C256 bootrom. It can be written by XTIDECFG.COM.
With "MEMVIEW.EXE" I can see the time running at adress 7FFF.

[640-KB]

Is it possible to add support for Dallas DS1644 Timekeeper?
This device has 32kb RAM suitable for holding the option-ROM, and a RTC!
I pluged this device as a 28C256 bootrom. It can be written by XTIDECFG.COM.
With "MEMVIEW.EXE" I can see the time running at adress 7FFF.

That's a fascinating chip. I had not come across that one before. So it's just memory address space mapped for R/W?

What kind of card do you have and do you know of any for sale I could get for testing? :)

[Batsch69]

I use a XT-IDE-card jumped for 28c256 ROM at 0xd800. The time is running at 0xdfff:0000.

[640-KB]

I use a XT-IDE-card jumped for 28c256 ROM at 0xd800. The time is running at 0xdfff:0000.

Oh, I understand now. The IC just intercepts those addresses for its I/O.

For sure then. I'll look into this. Thanks for the suggestion!