On Thursday, September 2, 2021 at 8:16, Gavin Scott via cctech wrote:
P.S. The HP Museum has the CE handbook for the 37 and
Micro 3000, but
it's in the 3000 Micro XE section. You can find it by searching within
the Documents page linked at the bottom of the left side navigation
bar.
3000-37-MicroFamily_CEServiceHandbook_30457-90039_200pages_Feb89.pdf
Page 5-31 of that manual details the LED display codes.
Note also that the Series 37 requires certain PCAs to be in certain slots
(pages 3-2 and 3-4), so it would be good to verify this too.
And as Gavin mentions, the CPU tries to talk to the terminal after
completing the self-test, so it's important to have a working terminal
connected and turned on when powering up the system.
-- Dave