<wolfspraul>
the idea is to add a 4.7k pullup on CE0 and WE# of the nor flash
<wolfspraul>
Werner is currently investigating whether that fixes anything, but from the datasheet it definitely looks like the right thing to do
<wolfspraul>
so the question for you right now is:
<wolfspraul>
can you find out how difficult it is to rework existing rc3 boards by adding a 0402 resistor in those 2 places?
<wolfspraul>
we don't know yet whether we want to do it, just collecting data points
<aw>
those two pins are hard to solder since there's no alternative pads ONLY nor chip's pins on WE#(pin 55), and CE0(pin 54)
<aw>
we're accumulating a total 70pcs "Avail-fix2b-l3" h/w patches with short L3 and lockflash version of flash version.
<aw>
70pcs here includes 25pcs "Packed - For Sale" and those ones sent out. With Werner's auto testing idea to verify if those two pull high resistors can suffer from exponential distribution and temperature-oriented later. :-)
<aw>
even if the results are good for fixing, the required fixes about two 0402 resistors I currently don't have idea to easily rework them in one batch time. ;-)
<wolfspraul>
wait
<aw>
but it's good that one pointed. :-)
<wolfspraul>
we don't know much about CE0 and WE# yet
<wolfspraul>
just collecting data
<aw>
sure
<wolfspraul>
I am not worried about the units we are testing, packing and shipping now
<wolfspraul>
we can definitely add CE0/WE# to the rc4 list
<aw>
yup...but I checked already that about the reworks if needs later. like i said, it's quite a hard though. :-)
<aw>
sure
<wolfspraul>
then before we finalize rc4, we need to make a design verification on at least one rc3 board that those 2 pullups will not cause problems
<wolfspraul>
so you can definitely already write down a note in the rc3 errata about ce0/we#, so we don't forget
<aw>
Christopher Adams will come here soon. ;-)
<wolfspraul>
the other question is whether we should fix it on rc3 boards
<aw>
sure okay...
<wolfspraul>
for that, let's see what werner finds out about them first
<wolfspraul>
so you have to solder the resistor directly onto the feet of the nor chip?
<wolfspraul>
and then a wire running somewhere, or no wire?
<wpwrak>
yeah. and add a little wire to 3.3 V
<wpwrak>
i'm actually more worried about the wire than about soldering to the NOR
<wolfspraul>
can the resistor be on the other side of the wire?
<wpwrak>
yes. that would be an option
<aw>
yup...wait couples days after his results are if related to remaining considerations.
<wolfspraul>
how long is the wire?
<wpwrak>
could be just a few mm, to the next point that has 3.3 V
<wolfspraul>
aw: ok, so right now only this for you: write down ce0/we# into the rc3 errata
<aw>
must have two small wires to VCC and connects 0402's one terminal pad then solder to nor's two pins
<wolfspraul>
aw: maybe the resistor can be on the other side of the wire, not directly at the nor pins
<aw>
wpwrak, this fix for me or you may not have problems on soldering, but i really have no gurantee on the quality though.
<aw>
soldering one board to have design validation is good to synchronize together
<aw>
but even if your results are great enough about two resistors, i still no confidence on such two. :-) I am serious.
<wolfspraul>
sure understand
<wolfspraul>
aw: first step: add to rc3 errata
<aw>
okay
<wolfspraul>
werner will verify whether they improve anything, or add regressions
<wolfspraul>
eventually sebastien will have a chance to quickly look at and double-check this idea
<wolfspraul>
for rc4, it's already clear we want this unless we find regressions
<wpwrak>
aw: (quality of rework) yes, that would be my concern, too. it would be fragile in the best case. one light touch, and it would break
<wolfspraul>
for rc3, right now it looks like we will not add them
<aw>
yup...i quitely prefer not to add those two resistors added to nor's two pins. it's not about i don't want to do. it's most related to that I am not sure those two wires connected to nor pins will break easily or not.
<aw>
so i suggest to apply this to rc4 once Werner's result about this is good, and surely I can add this patch to mine and later confirm with that.
<wpwrak>
sounds good to me
<wolfspraul>
I think we should skip the standby state when booting, i.e. when powered arrives over the DC cable, M1 should immediately boot all the way to rendering.