annotate doc/C139-notes @ 276:4221c724c664

R2D: preparations for adding LCD hardware suspend handling
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 07 Sep 2021 21:05:38 +0000
parents a62e5bf88434
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
50
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 FC Tourmaline firmware differs from Magnetite in two principal ways when it
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 comes to Mot C139 target support:
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 * C139 LCD support is implemented in a more forward-looking manner: instead of
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 emulating TI's C-Sample at the lowest R2D driver level and therefore being
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 forever limited to 84x48 pixel display size, Tourmaline implements a new
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 96x64 pixel framebuffer, matching the native LCD size of C1xx phones. The UI
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 configuration is still black&white only though - the Mother of FreeCalypso
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 has no current plans to support color UI on smaller LCD sizes than TI's
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 original 176x220 pix.
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 * Our aftermarket FFS configuration has been changed from 64x3 at 0x3C0000 to
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 64x7 at 0x300000. Our earlier 64x3 config was chosen back in 2015, at that
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 time we didn't know how much room we would end up needing for the firmware
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 image vs. how much FFS content we would eventually have, and this 64x3 config
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 is now deemed to be too small, allowing only one 64 KiB sector for FFS
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 content. Our new FC Tourmaline aftermarket FFS config supports up to 320 KiB
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 of FFS content, matches what we use on other platforms with 4 MiB flash chips,
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 leaves 3 MiB for the firmware image (our current smallbw UI fw is only 2 MiB),
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 and still avoids intersection with Motorola's (or rather Compal's) original
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 FFS, which is important for avoiding problems in converting C139 phones back
a62e5bf88434 first round of documentation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 and forth between Motorola and FreeCalypso firmwares.