Checkout my latest module for swordfish here -> MS5540C
This module is setup to use the software shift commands to communicate via the SPI interface of the MS5540C pressure and temperature sensor (Barometer). Overall, the sensor works great and I plan on integrating this with a SHT11 humidity and temperature sensor for some upcoming weather station work.
This sensor compares favorably with the SCP1000 pressure sensor, but has a much friendlier SMT package. I would recommend running an external 32.768 KHz oscillator as referenced in the schematic above, however, some forums have reported that the hardware pwm port of the pic could be configured to proved the necessary MCLK signal when running at a 50% duty cycle.
!!!MS5540C Barometer Module Announcement!!!
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