Tag: OEC12C887A

Odin/Dallas RTC module…from AliExpress (WHL #107F1)

Two weeks ago, I wrote about a Dallas/Odin RTC module with integrated battery that caused me some trouble on an old Pentium board. The BIOS defaults to no hard disks, and the module isn’t rechargeable, so once it’s empty, the board will no longer be able to boot directly from hard disk. So I checked my options…and bought from AliExpress, because I was feeling adventurous :)

2.14€ and a tad over a week later, this “OEC12C887A” module (matching the old one) showed up on some pink ESD-ish foam:

I mean…it does say Odin OEC12C887A on the housing, and they sure got a nice laser labelling machine…but…

Aren’t they ashamed of their shoddy refurbishment? […]

30th March 2025 30th March 2025 By Bzzz In No Comment

Odin/Dallas RTC modules with integrated battery (WHL #107)

Have you ever desoldered one of those ancient RTC modules from an equally ancient PC mainboard?
There was a time in the 1990s where board manufacturers abandoned the old leaky NiCd buffering cells and instead of hopping onto the CR2032 lithium train. They used Dallas modules (back when Dallas was still Dallas and not Maxim…which also ceased to exist in 2021 when they were bought by Analog) that served as real time clocks and battery backed SRAM for some 100 bytes of BIOS settings.
Well yeah, these are terrible as the battery isn’t replaceable since it is moulded into the bulky case. […]

16th March 2025 16th March 2025 By Bzzz In 3 Comments