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Additional Sensors |
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The sensor kit contains 2 sensors with analogue to digital conversion on the sensor chip (DS18b20 and DHT11) while for other analogue signals an additional external ADC is needed. |
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< < | The additional sensor boards are all based on the I2C bus and include |
> > | The additional sensor boards are all based on the I2C bus and include |
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- The PCF8591 8 bit A/D and D/A converter
The ADC has 4 multiplexed input channels and 2 DAC channel and it includes a potentiometer, a photo resistor and a thermistor, which can be connected to the ADC inputs through jumpers.
- The ADS1115 16 bit ADC
This is a high resolution ADC again with 4 multiplexed input channels
- The DS1307 Real Time Clock combined with the AT24c32 serial EEPROM
- The MCP4725 Digital to Analogue converter
- The BMP180 Temperature and Barometric Pressure sensor
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- The HD44780 LCD controller with a 2 x 16 character display and a PCF8574 8bit I/O expander for the I2C bus
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- The HD44780 LCD controller with a 2 x 16 character display and a PCF8574 8bit I/O expander for the I2C bus
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< < | The Raspberry Pi uses I2C bus 1 for communication with external I2C devices. This can be seen in the /dev directory. Both libraries: wiringpi and pigpio provide access functions to drive the I2C bus. The i2cdetect command allows to see which I2C addresses are in use. The screen dump below shows 2 devices connected to the I2C bus on address 0x3f ( the pcf8574 I/O expander used to driver the hd44780 display driver) and 0x48 (the pcf8591 A/D and D/A chip). |
> > | The Raspberry Pi uses I2C bus 1 for communication with external I2C devices. This can be seen in the /dev directory. Both libraries: wiringpi and pigpio provide access functions to drive the I2C bus. The i2cdetect command allows to see which I2C addresses are in use. The screen dump below shows 2 devices connected to the I2C bus on address 0x3f ( the pcf8574 I/O expander used to driver the hd44780 display driver) and 0x48 (the pcf8591 A/D and D/A chip). |
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