Uses a standard 2 x 20 character LCD module for readout of compass module CMPS03 and ambient temperature sensor LM35. Backlight switches on automatically using an LDR. Display of compass is controlled by a PIC16F877.
How does it work?
The microcontroller 16F877 does most of the job, once again.
1* Driving the LCD module type 2×20 characters with backlight This takes 12 data-lines (see basic schematic.)
2* Interfacing the CMPS03 module. We use the I²C interface for maximum resolution. This data is then converted to decimal and sent to the LCD.
3* Analog to digital conversion from temperature (LM35) and light (LDR) sensors.
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