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@ -72,7 +72,7 @@ The voltage that comes out the sensor is then read by the IoT device, and the de

 #### Analog to digital conversion

-IoT devices are digital - they can't work with analog values, they only work with 0s and 1s. This means that analog sensor values need to be converted to a digital signal before they can be processed. Many IoT devices have analog-to-digital converters (ADCs) to convert analog inputs to digital representations of their value. Sensors can also work with ADCs via a connector board. For example, in the Seeed Grove ecosystem with a Raspberry Pi, analog sensors connect to specific ports on a 'hat' that sits on the Pi connected to the Pi's GPIO pins, and this hat has an ADC to convert the voltage into a digital signal that can be sent ofsf the Pi's GPIO pins.
+IoT devices are digital - they can't work with analog values, they only work with 0s and 1s. This means that analog sensor values need to be converted to a digital signal before they can be processed. Many IoT devices have analog-to-digital converters (ADCs) to convert analog inputs to digital representations of their value. Sensors can also work with ADCs via a connector board. For example, in the Seeed Grove ecosystem with a Raspberry Pi, analog sensors connect to specific ports on a 'hat' that sits on the Pi connected to the Pi's GPIO pins, and this hat has an ADC to convert the voltage into a digital signal that can be sent off the Pi's GPIO pins.

 Imagine you have an analog light sensor connected to an IoT device that uses 3.3V, and is returning a value of 1v. This 1v doesn't mean anything in the digital world, so needs to be converted. The voltage will be converted to an analog value using a scale depending on the device and sensor. One example is the Seeed Grove light sensor which outputs values from 0 to 1,023. For this sensor running at 3.3V, a 1v output would be a value of 300. An IoT device can't handle 300 as an analog value, so the value would be converted to `0000000100101100`, the binary representation of 300 by the Grove hat. This would then be processed by the IoT device.