Updated STM32 ADC driver

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4189 42af7a65-404d-4744-a932-0658087f49c3

examples/README.txt

@@ -44,8 +44,10 @@ examples/adc
       and this value is ignored.  Otherwise, this number of samples is
       collected and the program terminates.  Default:  Samples are collected
       indefinitely.
-    - CONFIG_EXAMPLES_ADC_SAMPLESIZE - The number of bytes to read in one sample.
+    - CONFIG_EXAMPLES_ADC_GROUPSIZE - The number of samples to read at once.
-      Default: 8
+      Default: 4
+    - CONFIG_EXAMPLES_ADC_SAMPLEWIDTH - The width (in bits) of the on ADC sample.
+      Default: 16
 
 examples/buttons
 ^^^^^^^^^^^^^^^^

examples/adc/adc.h

@@ -54,8 +54,10 @@
  *   and this value is ignored.  Otherwise, this number of samples is
  *   collected and the program terminates.  Default:  Samples are collected
  *   indefinitely.
- * CONFIG_EXAMPLES_ADC_SAMPLESIZE - The number of bytes to read in one sample.
+ * CONFIG_EXAMPLES_ADC_GROUPSIZE - The number of samples to read at once.
- *   Default: 8
+ *   Default: 4
+ * CONFIG_EXAMPLES_ADC_SAMPLEWIDTH - The width (in bits) of the on ADC sample.
+ *   Default: 16
  */
 
 #ifndef CONFIG_ADC
@@ -66,10 +68,43 @@
 #  define CONFIG_EXAMPLES_ADC_DEVPATH "/dev/adc0"
 #endif
 
-#ifndef CONFIG_EXAMPLES_ADC_SAMPLESIZE
+#ifndef CONFIG_EXAMPLES_ADC_GROUPSIZE
-#  define CONFIG_EXAMPLES_ADC_SAMPLESIZE 8
+#  define CONFIG_EXAMPLES_ADC_GROUPSIZE 4
 #endif
 
+#ifndef CONFIG_EXAMPLES_ADC_SAMPLEWIDTH
+#  define CONFIG_EXAMPLES_ADC_SAMPLEWIDTH 16
+#endif
+
+/* Sample characteristics ***************************************************/
+
+#undef ADC_SAMPLE_BYTEWIDTH
+#if CONFIG_EXAMPLES_ADC_SAMPLEWIDTH <= 8
+#  undef CONFIG_EXAMPLES_ADC_SAMPLEWIDTH
+#  define CONFIG_EXAMPLES_ADC_SAMPLEWIDTH 8
+#  define ADC_SAMPLE_BYTEWIDTH 1
+#  define SAMPLE_FMT "%02x"
+#elif CONFIG_EXAMPLES_ADC_SAMPLEWIDTH <= 16
+#  undef CONFIG_EXAMPLES_ADC_SAMPLEWIDTH
+#  define CONFIG_EXAMPLES_ADC_SAMPLEWIDTH 16
+#  define ADC_SAMPLE_BYTEWIDTH 2
+#  define SAMPLE_FMT "%04x"
+#elif CONFIG_EXAMPLES_ADC_SAMPLEWIDTH <= 24
+#  undef CONFIG_EXAMPLES_ADC_SAMPLEWIDTH
+#  define CONFIG_EXAMPLES_ADC_SAMPLEWIDTH 24
+#  define ADC_SAMPLE_BYTEWIDTH 3
+#  define SAMPLE_FMT "%06x"
+#elif CONFIG_EXAMPLES_ADC_SAMPLEWIDTH <= 32
+#  undef CONFIG_EXAMPLES_ADC_SAMPLEWIDTH
+#  define CONFIG_EXAMPLES_ADC_SAMPLEWIDTH 32
+#  define ADC_SAMPLE_BYTEWIDTH 4
+#  define SAMPLE_FMT "%08x"
+#else
+#  error "Unsupported sample width"
+#endif
+
+#undef ADC_SAMPLE_SIZE (CONFIG_EXAMPLES_ADC_GROUPSIZE * ADC_SAMPLE_BYTEWIDTH)
+
 /* Debug ********************************************************************/
 
 #ifdef CONFIG_CPP_HAVE_VARARGS
@@ -94,6 +129,18 @@
  * Public Types
  ****************************************************************************/
 
+#if CONFIG_EXAMPLES_ADC_SAMPLEWIDTH == 8
+typedef uint8_t adc_sample_t;
+#elif CONFIG_EXAMPLES_ADC_SAMPLEWIDTH == 16
+typedef uint16_t adc_sample_t;
+#elif CONFIG_EXAMPLES_ADC_SAMPLEWIDTH == 24
+typedef uint32_t adc_sample_t;
+#elif CONFIG_EXAMPLES_ADC_SAMPLEWIDTH == 32
+typedef uint32_t adc_sample_t;
+#else
+#  error "Unsupported sample width"
+#endif
+
 /****************************************************************************
  * Public Variables
  ****************************************************************************/
@@ -111,6 +158,6 @@
  *
  ****************************************************************************/
 
-void adc_devinit(void);
+int adc_devinit(void);
 
 #endif /* __APPS_EXAMPLES_ADC_ADC_H */

examples/adc/adc_main.c

@@ -94,8 +94,9 @@
 
 int MAIN_NAME(int argc, char *argv[])
 {
-  uintt_t sample[CONFIG_EXAMPLES_ADC_SAMPLESIZE];
+  uint8_t sample[ADC_SAMPLE_SIZE];
   ssize_t nbytes;
+  FAR adc_sample_t *ptr;
 #if defined(CONFIG_NSH_BUILTIN_APPS) || defined(CONFIG_EXAMPLES_ADC_NSAMPLES)
   long nsamples;
 #endif
@@ -131,6 +132,7 @@ int MAIN_NAME(int argc, char *argv[])
       errval = 1;
       goto errout;
     }
+  message(MAIN_STRING "Hardware initialized. Opening the ADC device\n");
 
   /* Open the ADC device for reading */
 
@@ -147,6 +149,8 @@ int MAIN_NAME(int argc, char *argv[])
    * ADC samples.
    */
 
+  message(MAIN_STRING "Entering the main loop\n");
+
 #if defined(CONFIG_NSH_BUILTIN_APPS)
   for (; nsamples > 0; nsamples--)
 #elif defined(CONFIG_EXAMPLES_ADC_NSAMPLES)
@@ -161,10 +165,10 @@ int MAIN_NAME(int argc, char *argv[])
 
     msgflush();
 
-    /* Read one sample */
+    /* Read one sample of size ADC_SAMPLE_SIZE */
 
-    nbytes = read(fd, sample,CONFIG_EXAMPLES_ADC_SAMPLESIZE ));
+    nbytes = read(fd, sample, ADC_SAMPLE_SIZE);
-    ivdbg("Bytes read: %d\n", nbytes);
+    message("Bytes read: %d\n", nbytes);
 
     /* Handle unexpected return values */
 
@@ -181,10 +185,10 @@ int MAIN_NAME(int argc, char *argv[])
 
         message(MAIN_STRING "Interrupted read...\n");
       }
-    else if (nbytes != CONFIG_EXAMPLES_ADC_SAMPLESIZE)
+    else if (nbytes != ADC_SAMPLE_SIZE)
       {
         message(MAIN_STRING "Unexpected read size=%d, expected=%d, Ignoring\n",
-                nbytes, CONFIG_EXAMPLES_ADC_SAMPLESIZE);        
+                nbytes, ADC_SAMPLE_SIZE);        
       }
 
     /* Print the sample data on successful return */
@@ -192,16 +196,17 @@ int MAIN_NAME(int argc, char *argv[])
     else
       {
         message("Sample :\n");
-        for (i = 0; i < CONFIG_EXAMPLES_ADC_SAMPLESIZE; i++)
+        ptr = (FAR adc_sample_t*)sample;
+        for (i = 0; i < CONFIG_EXAMPLES_ADC_GROUPSIZE; i++)
           {
-            message("%d: %02x\n", i, sample[i]);
+            message("%d: " SAMPLE_FMT "\n", i, ptr[i]);
           }
       }
   }
 
 errout_with_dev:
   close(fd);
-errout_with_dev:
+
 errout:
   message("Terminating!\n");
   msgflush();