SPARCstation 20 with SCSI2SD
Maciej W. Rozycki
macro at linux-mips.org
Sun Dec 2 05:10:22 CST 2018
On Sat, 1 Dec 2018, alan--- via cctalk wrote:
> I'm not sure what the 'B' in the middle means (silicon rev?), but the DS12885
> has been around for decades. I use them the JR-IDE project.
Yes, the DS12885 is a standard part, still in production (with a trailing
+ marking RoHS compliance).
According to its datasheet the DS12B887 has an NC pin actually present in
the position where the DS12885 has the RESET# line, while the remaining NC
positions are absent due to the respective pins having been bent up (or
"are missing by design", as the datasheet puts it). So either a different
core had to be used with the DS12B887 or the datasheet has an error.
However RESET# would have to be connected to VCC for normal operation and
there is no mention of an internal pull-up on RESET# with the DS12885, so
I take it the DS12B887 had to use a different core and a DS12B885 seems
like a logical match.
The placement of RESET# right in the middle between VBAT and GND makes it
highly unlikely an internal discrete connection has been made in the
DS12B887 package between RESET# and VCC, as a shortage to the embedded
lithium cell from that pin if bent up and soldered to would be virtually
More information about the cctech