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annotate lunalcd2/README @ 71:31c8b1291b4a

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lunalcd3 project started
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 18 Nov 2021 04:59:47 +0000
parents a2ce85275f63
children
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a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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1 Formike KWH020ST23-F01 is a candidate LCD module being considered for our
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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2 FreeCalypso Libre Dumbphone dream handset. Prior to building the actual
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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3 handset, we will need to build our FC Venus development board, and prior to
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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4 starting the design of this Venus board, we are going to test the proposed LCD
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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5 module in our currently existing Luna environment. The modular LCD subsystem
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 board being designed in this directory is intended to be a drop-in replacement
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 for our previous Luna LCD board from 2020-04 (lunalcd1 directory), to be
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 connected to the same Caramel/C2 motherboards, with the resulting system
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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9 configuration still being Luna (not Venus).
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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10
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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11 In addition to changing out the LCD module, the backlight driver circuit is
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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12 being changed to the MAX1916-based one described in FreeCalypso Handset
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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13 Specification section 1.4.4, with a set of DIP switches selecting different LED
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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14 currents - the intent is to find appropriate LED currents for the different
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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15 display brightness modes that will be needed in the actual handset. A current
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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16 measurement resistor is also being inserted in the LCD (not backlight) power
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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17 supply path - we will be exercising the LCD controller/driver chip's power-
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
parents:
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18 saving sleep modes, and we need to be sure that they actually reduce the 2.8V
a2ce85275f63 lunalcd[12]/README written
Mychaela Falconia <falcon@freecalypso.org>
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19 supply current draw as expected.