From: "Ethan Dicks" <erd_6502(a)yahoo.com> While attempting to revive a Compaq 286/SLT laptop for use as a front-end for my UP600a programmer, I have found that the battery on the DS1287 has died (no suprise there). What sucks is that even after I run the floppy-based setup utility, after a reboot (not a power-off cycle), the machine forgets what I just set, both the data and time, and the geometry of the A: drive. Seeing as how it thinks there's a 5.25" floppy and it's really a 3.5" high-density drive at the end of the cable, as you can imagine, it won't reliably read disks. So... I have ordered a replacement DS12887 since they no longer make/ship the DS1287. Couple of interesting app notes here: http://www.maxim-ic.com/appnotes.cfm/appnote_number/562 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2681 What I'm wondering is if anyone on the list has ever replaced a DS1287 with a DS12887. One of the sheets seems to suggest that I'll need an updated BIOS ROM (clearly not available for a 286 laptop) to drive the extra stuff associated with the enhanced century rollover. Alternatively, has anyone here successfully performed surgery on a Dallas module? I have disconnected the battery from a Mostek 48T02 from a SPARC and soldered on an external Lithium cell, but the packaging makes it easy to get access to the battery wires coming down from the top (I even put the battery on a 9V battery snap so it's easier to replace) I haven't heard of anyone doing this for the more sealed Dallas modules. So... anybody else suffer though this? -ethan