# HG changeset patch # User Michael Spacefalcon # Date 1375047487 0 # Node ID 8e4dac492552d67497193b6da0f275d9d1bf6f6a # Parent 00dedefbdfd18c3ac9f2e5f656756fce426aed18 another Pirelli PCB tracing session, focusing on the display subsystem diff -r 00dedefbdfd1 -r 8e4dac492552 pirelli/calypso --- a/pirelli/calypso Fri Jul 26 03:15:57 2013 +0000 +++ b/pirelli/calypso Sun Jul 28 21:38:07 2013 +0000 @@ -1,3 +1,6 @@ +BGA orientation: A1 is the LR corner in steve-m's L1 picture. Row A is on the +bottom; row P is on the top; column 1 is on the right; column 14 is on the left. + Calypso pin I thought was nIBOOT (N1), but actually seems to be A13 (RFEN): the trace from the ball goes straight down to a via, L1 image coords (3676,1174). On L2 trace goes to another via at (3234,1074). On L5 it goes diff -r 00dedefbdfd1 -r 8e4dac492552 pirelli/pcb --- a/pirelli/pcb Fri Jul 26 03:15:57 2013 +0000 +++ b/pirelli/pcb Sun Jul 28 21:38:07 2013 +0000 @@ -8,6 +8,6 @@ any at all, other than maybe the grounding ones around the edges of the board. Instead most/all internal vias are blind, spanning from L2 through L7. At both surfaces there are micro-vias (with many/most of them one can't even -see the hope in steve-m's pictures, only a copper circle which one has to +see the hole in steve-m's pictures, only a copper circle which one has to infer is an "annulus" for a micro-via), and these micro-vias only go one layer deep: from L1 to L2, and from L8 to L7. diff -r 00dedefbdfd1 -r 8e4dac492552 pirelli/spca --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/pirelli/spca Sun Jul 28 21:38:07 2013 +0000 @@ -0,0 +1,50 @@ +Tracing signal from Calypso A1 (address line 1, ball F2); expecting to see it go +to ball H8 on SPCA552E. On L1 the trace goes to (4326,756). On L2 I see it +branching - d'oh, it's address line A1, of course it will go to a ton of things! +Looking for another signal to trace that would be point-to-point from Calypso +to SPCA552E. + +Let's try tracing the bypass GPIO signal, presumably originating from GPIO 7 on +the Calypso. That's Calypso ball N2. L1 goes to (4259,467). L2 takes it to an +inner via at (4290,471). Found it on L5: goes to another inner via at +(4370,1835). Found it on L7: goes to (4270,2026). On L8 it arrives at an SPCA +ball which we are going to assume is A8 (bypass input according to the Nokia +schematic). + +Deduced SPCA552E BGA orientation in steve-m's L8 picture: A1 in the LL corner, +row A along the bottom. + +Accessible surface test points around the SPCA: + +* Along the bottom (the side toward the red and # keys) we have TPs for A8 +(bypass input) and C7 (Rxd1). The TP in between these two seems to be connected +through some inner layer, haven't traced yet. The L8 coordinates of this TP are +(4221,2119). The hole seems to be slanted to (4228,2112) though. +On L7 it goes to a large-looking via at (4196,1966). + +* On the side toward the antenna we have TPs for C2 (LcmCs) and D3 (LcmWr). + +* On the side toward the USB port we have TPs for J8 (Txd1) and H9 (HstRd_n). + +* On the side toward the green and * keys we have TPs for G4 (Suspend), + H5 (Trap), and J7 (LcmVs). + +The L8 trace from ball H6 (LcmMck) goes in two directions, terminating at via +points (4066,1704) and (4270,1251). On L7 the leg from (4066,1704) goes to +(3722,1700), looks like a micro-via back to L8. + +Tracing Calypso PWL signal, starting with Calypso ball L7. On L1 the trace from +ball L7 appears to go to (3988,528); the trace from ball K7 (PWT/BU, no other +functions listed in CAL000) goes to (4041,813). + +Tracing the mysterious PWT/BU first. On L2 the trace from (4041,813) goes to +(4211,1018), seems to be a micro-via back to L1. On L1 it goes to some strange +component pad at (4300,1186). The component seems to be a resistor; the other +side connection is unclear. + +Back to PWL. On L2 the trace from (3988,528) goes to a larger via at +(4010,554). Found in on L7: goes to a micro-via to L8 at (3975,478). On L8 it +goes to another via back to L7 at (3784,664). On L7 it goes to a larger via at +(3635,839). Found it on L5: goes to another via at (3512,1808). Found it on +L7: goes to a micro-via to L8 at (3459,1756). There it appears to connect to +the mysterious A3-90E component through some resistors.