[uCsimm] Fried uCSimm?

From: Carl_Holmberg (cmholm@apple20.mhpcc.edu)
Date: Mon Feb 28 2000 - 19:49:13 EST


If I've damaged the uCsimm itself, what might some symtoms be?

When I first assembled the ugardener board, I reversed the polarity of the pins on
the R Shack adjustable wall wort and killed the voltage regulator. To up the ante, I
repowered the board with the uCsimm on board, and got zippo over the tty and
ethernet. Power in prototyping area at ~5v. Oops. Ordered three replacement
regulators from Digikey and waited.

Two months later (yesterday) put in a new regulator, switched the wall wort polarity
to negative center pin, and took the unit for a spin. Power in prototyping area
~3.2v. Power down and attach uCsimm, tty, and ethernet. Power on, das blinkenlights
(not steady) on enet hub, ~3.2v in prototyping (gotta get some clip on probes!) and
life on the tty...

uCbootstrap v1.0 (c) Copyright 1999 Rt-Control All Rights Reserved

FLASH type 2249 [AM29LV160B]
DP|004000 DP|006000 DP|008000 DP|010000 D-|020000 D-|030000
D-|040000 D-|050000 D-|060000 D-|070000 D-|080000 D-|090000
D-|0a0000 D-|0b0000 D-|0c0000 D-|0d0000 D-|0e0000 D-|0f0000
D-|100000 D-|110000 D-|120000 D-|130000 D-|140000 D-|150000
D-|160000 D-|170000 D-|180000 D-|190000 D-|1a0000 D-|1b0000
D-|1c0000 D-|1d0000 D-|1e0000 D-|1f0000 D-|200000

B$

...which repeats for as long as it's powered up. The regulator still gets warm, so I
don't leave it on for more than a minute at a time. After a particular boot up
attempt, it stopped at 'B$':

B$ ((Stops at this point, so I hit <cr>))

B$ g ((years of Macsbug lead me to try 'g'<cr>))

g: command not found

B$ ls ((I know the kernel can't be up yet, but what the hell))

ls: command not found

B$

uCbootstrap v1.0 (c) Copyright 1999 Rt-Control All Rights Reserved

((yada, yada, back to that cycle again))

Things I haven't yet done:
1) set my meter to measure min/max, is voltage dip causing repeated resets?
2) see if any solder flowed thru the gardener board and is shorting simm holder
pins.

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