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pigpio-master/EXAMPLES/Python/SENT_PROTOCOL/README.md

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+# Python Class for Reading Single Edge Nibble Transmission (SENT) using the Raspberry Pi
+
+A full description of this Python script is described at [www.surfncircuits.com](https://surfncircuits.com) in the blog entry: [Implementing a Single Edge Nibble Transmission (SENT) protocol in Python for the Raspberry Pi Zero](https://surfncircuits.com/?p=3725)
+
+
+This python library will read a Raspberry Pi GPIO pin connected. Start the pigpiod daemon with one microsecond sampling to read SENT transmissions with three microsecond tick times.   
+
+## To start the daemon on Raspberry Pi
+- sudo pigpiod -s 1
+
+## SENT packet frame summary
+
+- Sync Pulse: 56 ticks
+- 4 bit Status and Message Pulse: 17-32 ticks
+- 4 bit (9:12) Data1 Field: 17-32 ticks
+- 4 bit (5:8) Data1 Field: 17-32 ticks
+- 4 bit (1:4) Data1 Field: 17-32 ticks
+- 4 bit (9-12) Data2 Field: 17-32 ticks
+- 4 bit (5-8) Data2 Field: 17-32 ticks
+- 4 bit (1-4) Data2 Field: 17-32 ticks
+- 4 bit CRC: 17-32 ticks
+
+
+## requirements
+[pigpiod](http://abyz.me.uk/rpi/pigpio/)  library required
+
+## To run the script for a signal attached to GPIO BCD 18 (pin 12)
+- python3 sent_READ.py