SIEMENS (ROLM Systems) UM386-R 80386 Motherboards were the Planar Boards for the ROLM Voice Mail System. The motherboard you have (UM386-R) was from Replacement (Upgrade) Inventory, many NOS.
After IBM purchased ROLM (1984), the “new” ROLM Voice Mail System used IBM AT motherboards. I believe same as used in IBM 5162 (XT-286). IBM's ROLM division was later 50% sold to
Siemens AG in 1989,
and by 1992, Siemens bought out IBM's remaining share in ROLM.
Siemens dropped ROLM name in late 1990s (still retains copyright, brand name).
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This Siemens UM386-R Motherboard is Documented at The Retro Web
UM82C480 386/486 PC Chip Set. BIOS Image (AMI 1992) captured.
ROLM Systems (Siemens) UM386-R is a motherboard based on the UMC UM82C390 (40MHz 386 PC Chip Set) chipset. Get specs, BIOS, documentation and more!
theretroweb.com
Would the absence of battery prevent setup from running?
YES
Your Siemens UM386-R motherboard is likely BLANK, Replacement (NOS) Inventory.
Address the Missing CMOS memory battery,
the AMI BIOS has the built-in SETUP routine for function CMOS memory configuration.
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You need the 6 Volt CMOS Battery (non-Rechargable), common battery since 1984 with IBM AT (80286) and compatible motherboards (80386) that used 4-pin header (one pin missing/socket blocked for Polarity Keying).
You will find 3.6 Volt lithium memory batteries, BUT not ideal solution for 1990s 5 Volt memory ICs !!
IBM model 5170 (IBM AT, 1984) used IBM part number: 8286121 (discontinued)
Tadiran Batteries (Lake Success, NY) was one supplier, TL-5293/W
Tadiran pioneered the lithium thionyl chloride (LiSOCl2) battery for remote wireless applications. As the industry leader, Tadiran is dedicated to delivering ultra-long-life power for many different applications.
tadiranbat.com
That Tadrian battery is now discontinued, BUT various companies fabricate ($$) plug-in replacement.
In the IBM Model 5162 (XT/286) had a built-in holder for its 6V battery, type BR-P2 or CR-P2.
IF you desire to DIY fabricate the IBM 5162 battery holder solution,
THEN purchase the Memory Protection Devices (MPD) BH223-L battery holder for BR-P2
from Digi-Key (in stock at $5.15). Just add Dupont connector.
Keystone 2478, 4-cell “AAA” (in series 4+1.5V) battery holder with wire leads and
correct Dupont socket (See First Photo)
For 4 AA Cells-in Series-PN2478
www.keyelco.com
Can be found at computer shops since 1990s (Jameco has the “AAA” holders ‘On Clearance’).
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MINUS ZERO DEGREES — Knowledge-base for IBM Computers (Education thru History)
www.minuszerodegrees.net
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greg
chicago