annotate pirelli/fdp @ 402:1b83d07576bf

compal/boot/c123-boot.disasm: missed vector branch at 0x1c
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 15 Jan 2023 00:06:59 +0000
parents cbd944ebeff0
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
275
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 The trace from S71PL129NC0 ball D5 (flash reset) goes to a pull-up resistor and
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 to a microvia at (5130,717). On L7 this microvia connects to an inner via at
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 (5141,681). Found it on L2, trace from inner via goes to a microvia to L1 at
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 (4676,922). On L1 the trace goes to a pair of resistor footprints, the left
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 one is populated, the right one is not. Tracing the populated branch: the
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 trace goes to a microvia at (4516,1047). On L2 the microvia connects to an
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 inner via at (4540,1032). Found it on L4, the trace goes through another inner
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 via at (3718,1052) and finally to yet another inner via at (1699,1348).
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 Tracing the populated branch from (1699,1348): found it on L2, goes to a
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 microvia back to L1 at (1673,1352). It is TCXOEN!
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 Tracing the unpopulated resistor branch: microvia from L1 to L2 at (4665,892).
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 On L2 the trace goes two ways: to another microvia back to L1 at (4142,802) and
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 to an inner via at (5150,834). The microvia back to L1 at (4142,802) falls on
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 Calypso ball F4 - that's FDP! Tracing the inner via at (5150,834): found it on
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 L7, trace obscured by damage, apparently ends at (5169,751), there may have
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 been a microvia around (5166,709). It might be plausibly connected to the
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 WP#/ACC pin, which is also pulled up like RST#, but the damage makes it
cbd944ebeff0 Pirelli PCB RE: traced out Calypso FDP and flash reset input
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 impossible to trace for certain.