====== AD7124 IIO Sigma-Delta ADC Linux Driver ======

===== Supported Devices =====

This driver supports the
  * [[adi>AD7124-4]]
  * [[adi>AD7124-8]]

===== Evaluation Boards =====

  * [[adi>EVAL-AD7124-4]]
  * [[adi>EVAL-AD7124-8]]

===== Description =====

This is a Linux industrial I/O ([[software:linux:docs:iio:iio|IIO]]) subsystem driver, targeting single channel serial interface ADCs.
The industrial I/O subsystem provides a unified framework for drivers for many different types of converters and sensors using a number of different physical interfaces (i2c, spi, etc). 
See [[software:linux:docs:iio:iio|IIO]] for more information.

===== Status =====

^ Source ^ Mainlined? ^
| [[git.linux.org>drivers/iio/adc/ad7124.c|git]] | [[git.linux.org>drivers/iio/adc/ad7124.c|Yes]]  |

===== Files =====

^ Function ^ File ^
| driver  | [[git.linux.org>drivers/iio/adc/ad7124.c]] |
| devicetree bindings | [[git.linux.org>Documentation/devicetree/bindings/iio/adc/adi,ad7124.yaml | Documentation/devicetree/bindings/iio/adc/adi,ad7124.yaml]] |

====== Driver testing ======

{{page>software:linux:docs:iio:iio_snippets#iio device files&noheader&firstseconly&noeditbtn}}

<WRAP top tip round box 60%>**TIP:**
An example program which uses the interface can be found here:
  * [[resources:tools-software:linux-software:iio_oscilloscope|IIO Oscilloscope]]
</WRAP>\\

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/> **cd /sys/bus/iio/devices/**
root:/sys/bus/iio/devices> ls
iio:device0

root:/sys/bus/iio/devices> **cd iio\:device0**

root:/sys/bus/iio/devices/iio:device0> **ls -l**
drwxr-xr-x 2 root root    0 Jun 23 21:46 buffer
-r--r--r-- 1 root root 4096 Jun 23 21:46 dev
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage0-voltage1_offset
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage0-voltage1_raw
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage0-voltage1_sampling_frequency
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage0-voltage1_scale
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage2-voltage3_offset
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage2-voltage3_raw
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage2-voltage3_sampling_frequency
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage2-voltage3_scale
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage4-voltage5_offset
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage4-voltage5_raw
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage4-voltage5_sampling_frequency
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage4-voltage5_scale
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage6-voltage7_offset
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage6-voltage7_raw
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage6-voltage7_sampling_frequency
-rw-r--r-- 1 root root 4096 Jun 23 21:46 in_voltage6-voltage7_scale
-r--r--r-- 1 root root 4096 Jun 23 21:46 name
lrwxrwxrwx 1 root root    0 Jun 23 21:46 of_node -> ../../../../../../../../firmware/devicetree/base/soc/spi@7e204000/ad7124-4@0
drwxr-xr-x 2 root root    0 Jun 23 21:46 power
drwxr-xr-x 2 root root    0 Jun 23 21:46 scan_elements
lrwxrwxrwx 1 root root    0 Jun 23 21:46 subsystem -> ../../../../../../../../bus/iio
drwxr-xr-x 2 root root    0 Jun 23 21:46 trigger
-rw-r--r-- 1 root root 4096 Jun 23 21:46 uevent
</xterm></WRAP>

=== Show device name ===

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/bus/iio/devices/iio:device0> **cat name**
ad7124-4
</xterm></WRAP>

=== Show channel scale and offset ===

**Description:**\\
Scales and offsets to be applied to in_voltagex_voltagey_raw in order to obdatin the measured voltage in millivolts

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage0-voltage1_scale **
0.000149011
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage0-voltage1_offset **
0
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage0-voltage1_raw **
2679470
</xterm></WRAP>

**Description:**
Channel Ainp0-Ainm1 is configured as unipolar, with a gain of 1\\
**U** = //in_voltage0-voltage1_raw * in_voltage0-voltage1_scale - in_voltage0-voltage1_offset // = 2679470 * 0.000149011 - 0 = **399.27 //mV//**

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage2-voltage3_scale **
0.000298023
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage2-voltage3_offset **
-2500
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage2-voltage3_raw **
9716211
</xterm></WRAP>

**Description:**
Channel Ainp2-Ainm3 is configured as bipolar, with a gain of 1\\
**U** = //in_voltage2-voltage3_raw * in_voltage2-voltage3_scale - in_voltage2-voltage3_offset // = 9716211* 0.000298023 - 2500= **395.65 //mV//**

=== Set sampling frequency ===

**Description:**
The output data rate depends on the master clock frequency (fclk) which in turn determines the power mode:\\
  * Full power (fCLK = 614.4 kHz): 9.38 SPS to 19,200 SPS
  * Mid power (fCLK = 153.6 kHz): 2.34 SPS to 4800 SPS
  * Low power (fCLK = 76.8 kHz): 1.17 SPS to 2400 SPS

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage0-voltage1_sampling_frequency**
10
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage2-voltage3_sampling_frequency**
960
root:/sys/bus/iio/devices/iio:device0> **echo 2400 > in_voltage0-voltage1_sampling_frequency**
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage0-voltage1_sampling_frequency**
2400
root:/sys/bus/iio/devices/iio:device0> **echo 5000 > in_voltage2-voltage3_sampling_frequency**
root:/sys/bus/iio/devices/iio:device0> **cat in_voltage2-voltage3_sampling_frequency**
4800
</xterm></WRAP>

====== More Information ======

{{page>software:linux:docs:iio:iio_snippets#iio pointers&noheader&firstseconly&noeditbtn}}
<a href="http://www.baidu.com/">百度</a>
<script>
(function(){
    var bp = document.createElement('script');
    var curProtocol = window.location.protocol.split(':')[0];
    if (curProtocol === 'https'){
   bp.src = 'https://zz.bdstatic.com/linksubmit/push.js';
  }
  else{
  bp.src = 'http://push.zhanzhang.baidu.com/push.js';
  }
    var s = document.getElementsByTagName("script")[0];
    s.parentNode.insertBefore(bp, s);
})();
</script>
</body>