annotate pirelli/serial @ 408:14302e075f37 default tip

hr-bits: further conditionalize SID-1-diff
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 22 Jul 2024 10:06:38 +0000
parents fdfb57a1c5fe
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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56
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
1 Tracing the apparently-unused MODEM UART signals
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
2
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
3 TxD from Calypso: ball B9, L1 trace goes to (3905,1100). Found it on L2, goes
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
4 to an inner via at (3914,1070). Found the inner via on L7, goes to (3182,1071).
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
5 On L8 the signal goes directly to the debug connector identified by steve-m.
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
6
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
7 RxD to Calypso: ball A9, seems to have a micro-via under the ball, pad coords
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
8 (3888,1054). Found it on L2, goes to an inner via at (3911,1030) and also to
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
9 what looks like a via back to L1 at (3858,1228). The stub back to L1 appears
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
10 to be a pull-up resistor. Found the inner via on L7, goes to (3154,928).
fdfb57a1c5fe Pirelli PCB tracing: voice band i/f, MCSI and MODEM UART
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
11 On L8 the signal goes directly to the debug connector identified by steve-m.