ST ST7 - Display Circuit

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10 - Second Application: a Sailing Computer
10.3.1 Display circuit
10-schem
MOSI
(Pc5)
SCK
(Pc6)
ST
72311
4094 4094 4094 4094
3 LCD Modules, each driven by 4 shift registers
5v
Pd0
(ain)
1K
330
330
330
Push
buttons:
(2.49v)
(0x7f)
(1.99v)
(0x65)
(1.24v)
(0x3f)
5v
390
5v
390
5v
390
Pa4
Pa5
Pa6
(drain)
Sailing computer: principle of the digital display board
Wind
speed
Wind
angle
Boat
speed
Visible
(green)
Real
(red)
Visible
(green)
Real
(red)
VMG
(red)
Boat speed
(green)
-1st display: Visible / Real Wind speed
-2nd display: Visible / Real Wind angle
-3rd display: Boat Speed / VMG
First display
Pd2
Pd3
Pd4
5v
3x10K
Wind speed calibration
Boat speed calibration
Wind angle calibration
(ain)