TS-4100 ADC: Difference between revisions
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All of these inputs can sample 0-3.3 VDC natively or 4-20 mA with the necessary hardware in place. | All of these inputs can sample 0-3.3 VDC natively or 4-20 mA with the necessary hardware in place. | ||
{{Note|An external resistor will need to be added in order to enable | {{Note|An external resistor will need to be added in order to enable the 4-20 mA measurements.}} | ||
These ADCs are accessed through the [https://wiki.analog.com/software/linux/docs/iio/iio Linux Industrial I/O Subsystem] (IIO), which provides sample rates up to 6ksps across all inputs. | These ADCs are accessed through the [https://wiki.analog.com/software/linux/docs/iio/iio Linux Industrial I/O Subsystem] (IIO), which provides sample rates up to 6ksps across all inputs. |
Revision as of 19:22, 15 June 2020
This board supports two 12-bit ADC inputs using the i.MX6UL CPU's integrated ADC. All of these inputs can sample 0-3.3 VDC natively or 4-20 mA with the necessary hardware in place.
Note: | An external resistor will need to be added in order to enable the 4-20 mA measurements. |
These ADCs are accessed through the Linux Industrial I/O Subsystem (IIO), which provides sample rates up to 6ksps across all inputs. The simplest API it offers for slow speed acquisition is via sysfs (/sys):
cat /sys/bus/iio/devices/iio:device0/in_voltage{1,9}_raw
The pin assignments and names for accessing each ADC input are:
Schematic Name | i.MX6UL ADC Signal | CN2 Terminal Pin | IIO name |
---|---|---|---|
GPIO_1_ADC | ADC1_IN1 | 12 | voltage1 |
GPIO_9_ADC | ADC1_IN9 | 91 | voltage9 |
Note: | Each baseboards breakout implementation of these two ADC pins will differ. |