![]() The first stage is to remove the potted housing containing the cell and crystal, leaving pins protruding to which the new parts can be attached. It's not really a major issue as, although the system time is set from the real-time clock when the OS boots, correcting it is simply a matter of executing 'ntpdate' during system initialisation with a local or Internet NTP time-server specified. I'm currently reserving judgement on whether or not these are suitable, I'll have to observe how well it keeps time with the power off. Solder, soldering iron, patience, coffee, etc.īuried in ST Application Note AN934 TIMEKEEPER calibration I found: At STMicroelectronics, the real-time clock has an internal capacitance of 12.5pF (except for the M41T6x device, which has an internal capacitance of 6pF) across the crystal input pins.So I got watch crystals specified for a load capacitance of 12.5 pF.Surface-mount CR1632 coin-cell holder (Renata SMTU-1632-1). ![]() Here's the offending article this is one of the two from my SPARCserver 1000E.Īccording to ST Quality Note QNSR9701, the Date Code H994K 9440 and Encapsulation Code HT303 4A date it to 1994 no wonder it's dead! I've done several over the last decade and have refined my methods. So I thought I'd detail one of my recent attempts. Google brings up a few pages detailing repair of the things but some attempts look a little crude and at least one appears to discard the crystal, leaving the clock inoperative. There's more information in the Sun NVRAM/hostid FAQ, including how to reprogram new/repaired ones on several machines. It also appears that the design has been changed and some Suns refuse to work with the new ones. The system's MAC address, host ID and configuration information are stored in this NVRAM the lithium cell lasts around 10 years and, when it dies, causes all manner of problems including a MAC address of FF:FF:FF:FF:FF:FF and a system which won't boot. (Types include M48T02, M48T08, M48T18 earlier ones were prefixed 'MK'.) Old Suns (and a few other old machines) use a SGS-Thomson (formerly Mostek) 'Timekeeper' integrated SRAM, real-time clock, crystal and battery.
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