ADC overo 2.6.39+ - Revision history

Alxx: /* Python */

2011-09-21T07:11:19Z

‎Python

2011-09-21T07:10:12Z

‎Using the ADC's: fix formatting

2011-09-21T06:54:23Z

‎Using sysfs from c and fopen and fread

2011-09-21T06:54:02Z

‎Using sysfs from c and fopen and fread: code formating

2011-09-21T06:46:30Z

‎Using sysfs from c and fopen and fread

2011-09-21T06:45:58Z

‎Using sysfs in c and fopen and fread

2011-09-21T06:44:17Z

added brief example on reading adc's in c via fopen and fread

2011-09-19T08:12:14Z

‎Using the ADC's

2011-09-19T07:52:39Z

‎Using the ADC's

2011-09-19T07:50:33Z

‎ADC's via sysfs in code

@@ Line 30: / Line 30: @@
 === Python ===
-import os
+ import os
+ import sys
-import sys
+ import subprocess
+ cmd1 = "cat /sys/class/hwmon/hwmon1/device/in7_input"
-import subprocess
+ process = subprocess.Popen(cmd1, stdout=subprocess.PIPE , shell=True)
+ os.waitpid(process.pid, 0)[1]
-cmd1 = "cat /sys/class/hwmon/hwmon1/device/in7_input"
+ udata = process.stdout.read().strip()
+ print udata
 process = subprocess.Popen(cmd1, stdout=subprocess.PIPE , shell=True)
-−
 os.waitpid(process.pid, 0)[1]
-−
 udata = process.stdout.read().strip()
-−
 print udata
 '''In console (in interactive mode)'''
-python
+ python
+ Python 2.6.6 (r266:84292, Sep  1 2011, 13:08:10)
-Python 2.6.6 (r266:84292, Sep  1 2011, 13:08:10)
+ [GCC 4.3.3] on linux2
+ >>> import os
-[GCC 4.3.3] on linux2
+ >>> import sys
+ >>> import subprocess
->>> import os
+ >>> cmd1 = "cat /sys/class/hwmon/hwmon1/device/in7_input"
+ >>> process = subprocess.Popen(cmd1, stdout=subprocess.PIPE , shell=True)
->>> import sys
+ >>> os.waitpid(process.pid, 0)[1]
-−
->>> import subprocess
+ >>> udata = process.stdout.read().strip()
+ >>> print udata
 >>> cmd1 = "cat /sys/class/hwmon/hwmon1/device/in7_input"
+ >>>
 >>> process = subprocess.Popen(cmd1, stdout=subprocess.PIPE , shell=True)
-−
 >>> os.waitpid(process.pid, 0)[1]
-−
 ==Using sysfs from c and fopen and fread==

@@ Line 7: / Line 7: @@
 It is now even easier to access using the /sys/class interface:
-root@omap3-multi:~# ls /sys/class/hwmon/hwmon1/device/
+ root@omap3-multi:~# ls /sys/class/hwmon/hwmon1/device/
-driver          in12_input  in4_input  in8_input    subsystem
+  root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/temp1_input
-hwmon          in15_input  in5_input  in9_input    temp1_input
+  root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/curr10_input
+ -750
-in0_input     in2_input   in6_input  modalias    uevent
-−
-root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/temp1_input
-−
-−
-−
 root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/curr10_input
-−
 -750
 ==ADC's via a system call==

@@ Line 86: / Line 86: @@
   #include <stdio.h>
   #include <stdlib.h>
   #include <string.h>
   FILE *fp;

@@ Line 84: / Line 84: @@
 A much useful way to access the adc's is using fopen and fread.
-<nowiki>
+ #include <stdio.h>
-#include <stdio.h>
+ #include <stdlib.h>
-#include <stdlib.h>
+ #include <sys/types.h>
-#include <sys/types.h>
+ #include <sys/stat.h>
-#include <sys/stat.h>
+ #include <unistd.h>
-#include <unistd.h>
+ #include <fcntl.h>
-#include <fcntl.h>
+ #include <sys/mman.h>
-#include <sys/mman.h>
+ #include <time.h>
-#include <time.h>
+ #include <string.h>
-#include <string.h>
+ FILE *fp;
+ int main(void)
 FILE *fp;
-−
 int main(void)
-−
      char read_value[4];
      char adcVal2[6];
@@ Line 107: / Line 104: @@
+     }
      rewind(fp);
      fread(&read_value, sizeof(char), 1 , fp);
      strcpy(adcVal2 , read_value);
      fclose(fp);
      printf("\nADC 2 value = %s \n",adcVal2);
      return 0;
-−
+ }
-</nowiki>
 ==Building your own kernel ==

@@ Line 83: / Line 83: @@
 ==Using sysfs from c and fopen and fread==
 A much useful way to access the adc's is using fopen and fread.
 <nowiki>
 #include <stdio.h>

@@ Line 81: / Line 81: @@
 >>>
-==
+==Using sysfs in c and fopen and fread==
 ==Building your own kernel ==

@@ Line 2: / Line 2: @@
 From posts in the mailing list by Steve Sakoman and others
-In linux-omap3-2.6.39
+In linux-omap3-2.6.39 and 3.0 and above
 The madc driver is now upstream and in the process it moved to the hwmon subsystem.

@@ Line 31: / Line 31: @@
 os.system("cat /sys/class/hwmon/hwmon1/device/in7_input")
 === Python ===
@@ Line 82: / Line 80: @@
 ==
 ==Building your own kernel ==