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products:sbc:vim3:applications:gpio:adc

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products:sbc:vim3:applications:gpio:adc [2022/12/21 21:29]
ivan
products:sbc:vim3:applications:gpio:adc [2022/12/21 21:29] (current)
ivan [VIM3/3L ADC]
Line 3: Line 3:
 ====== VIM3/3L ADC ====== ====== VIM3/3L ADC ======
  
 +===== Introduction =====
 +
 +This documentation will introduce the usage of ADC.
 +
 +
 +===== Hardware Information =====
 +
 +The ADC  is a 12-bit successive approximation register (SAR) A/D Converter.
 +
 +^  Pin  ^ SIGNAL  ^  Voltage  ^  Device Node                                       ^
 +|  10   | ADC_CH0 |  0~1.8V    /sys/bus/iio/devices/iio:device0/in_voltage0_raw  |
 +|  12   | ADC_CH3 |  0~1.8V    /sys/bus/iio/devices/iio:device0/in_voltage3_raw  |
 +
 +===== Get Raw ADC Value =====
 +
 +<WRAP important >
 +Replace the variable ''x'' in ''in_voltageX''raw with the corresponding channel value
 +</WRAP>
 +
 +```shell
 +$ cat /sys/bus/iio/devices/iio:device0/in_voltageX_raw
 +```
 +
 +The following uses Pin10 as an example.
 +
 +```shell
 +$ cat /sys/bus/iio/devices/iio:device0/in_voltage0_raw     // pin10 is connected to 1.8V                                        
 +4082
 +$ cat /sys/bus/iio/devices/iio:device0/in_voltage0_raw    // pin10 connects to GND
 +0
 +```
 +
 +Convert the raw ADC value to Voltage:
 +
 +''Voltage = (value / 4096) * 1.8V''
Last modified: 2022/12/21 21:29 by ivan