FreeCalypso > hg > freecalypso-reveng

annotate pirelli/calypso @ 27:343b6b2f178b

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beginning of Mokopir-FFS verbal description
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Sun, 30 Jun 2013 01:17:30 +0000
parents b0f7481efc8b
children 8e4dac492552
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b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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1 Calypso pin I thought was nIBOOT (N1), but actually seems to be A13 (RFEN):
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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2 the trace from the ball goes straight down to a via, L1 image coords
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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3 (3676,1174). On L2 trace goes to another via at (3234,1074). On L5 it goes
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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4 to yet another via at (2950,535). On L4 it goes to (1941,457). On L2 it goes
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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5 to a surface via at (1957,484). Back on L1 it goes to Rita pin 2 (XEN).
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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6 This arrangement matches what the Rita spec describes as the "external VCTCXO"
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
7 configuration. In contrast, the Leonardo schematics depict the "internal
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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8 VCTCXO" configuration.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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9
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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10 Double-checking: in the "external VCTCXO" configuration Rita pin 1 (XSEL) is
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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11 supposed to be grounded. On L1 the pad appears to go nowhere (isolated).
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
12 The central coordinates of the pad on L1 are (1956,638). On L2 there is
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
13 solid copper fill in that area. Perhaps there is an invisible micro-via?
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
14
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
15 The real nIBOOT pin (N1): stays on L1, a trace takes it to one pad of a
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
16 2-pad SMT component, the other pad's connection is unclear (appears isolated,
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
17 must be an invisible micro-via). Must be a pull-up/down resistor, hopefully
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
18 pull-down.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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19
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
20 nCS0 (C2): L1 trace to (4262,1016). On L2 it goes to two via points:
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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21 (4852,1016), an obvious larger via, and (4802,1000), a spot where a micro-via
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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22 back to L1 could hide. The micro-via back to L1 appears to be there indeed,
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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23 feeding an unmasked test point on the surface. Back to the main trace at
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
24 (4852,1016): there's something on L4 (might be a trace to another nearby via),
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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25 but maybe it's nothing, just a poor picture. Most likely nothing there, as
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
26 the same arrangement appears on L5 and L6, but clearly with no connection
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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27 between the two nearby vias. L7 is probably where the interesting connection
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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28 is, but the trace appears to have been scraped off in that spot in steve-m's
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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29 layer-grinding process.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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30
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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31 Taking a different approach: let's start with the RAM/flash MCP on L8. Flash
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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32 CE1# goes to (4911,987); flash CE2# goes to (4954,660) and to an L8 test pad;
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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33 OE# goes to (4885,982); RAM CE1# goes to (4860,978). Of the two L2-L7 vias,
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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34 the upper one appears to be RAM, and the lower one appears to be flash.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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35
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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36 Mistake found: I had earlier messed up trying to trace nCS0 on L2. Now it's
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
37 all clear: nCS0 goes to flash CE1#.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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38
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
39 Now let's trace the RAM CS. From the upper L2-L7 via it goes on L2 to
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
40 (4800,1002) - already known to be a test point - and to (4212,978).
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
41 On L1 it goes to Calypso pin C3 - nCS1, just like on Leonardo.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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42
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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43 Now let's trace flash CE2#. L7-L8 via at (4954,660); L2-L7 via at (4965,927);
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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44 on L2 it goes to (4210,930), on L1 it goes to Calypso ball D3.
b0f7481efc8b Pirelli PCB rev eng: finally have something worthy to report:
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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45 That's nCS3.