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aio: add calls for changing bit value of the read

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Signed-off-by: Thomas Ingleby <thomas.c.ingleby@intel.com>
This commit is contained in:
Thomas Ingleby
2014-09-22 14:22:17 +01:00
parent dcc4efbaf8
commit 6a7add6b99
4 changed files with 82 additions and 7 deletions
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18
api/mraa/aio.h
View File

@@ -74,6 +74,24 @@ uint16_t mraa_aio_read(mraa_aio_context dev);
*/
mraa_result_t mraa_aio_close(mraa_aio_context dev);
/**
* Set the bit value which mraa will shift the raw reading
* from the ADC to. I.e. 10bits
* @param dev the analog input context
* @param bits the bits the return from read should be i.e 10
*
* @return mraa result type
*/
mraa_result_t mraa_aio_set_bit(mraa_aio_context dev, int bits);
/**
* Gets the bit value mraa is shifting the analog read to.
* @param dev the analog input context
*
* @return bit value mraa is set return from the read function
*/
int mraa_aio_get_bit(mraa_aio_context dev);
#ifdef __cplusplus
}
#endif

18
api/mraa/aio.hpp
View File

@@ -62,6 +62,24 @@ class Aio {
// Use basic types to make swig code generation simpler
return (int) mraa_aio_read(m_aio);
}
/**
* Set the bit value which mraa will shift the raw reading
* from the ADC to. I.e. 10bits
* @param bits the bits the return from read should be i.e 10
* @return mraa result type
*/
mraa_result_t set_bit(int bits) {
return mraa_aio_set_bit(m_aio, bits);
}
/**
* Gets the bit value mraa is shifting the analog read to.
*
* @return bit value mraa is set return from the read function
*/
int get_bit() {
return mraa_aio_get_bit(m_aio);
}
private:
mraa_aio_context m_aio;
};

1
include/mraa_internal_types.h
View File

@@ -76,4 +76,5 @@ struct _pwm {
struct _aio {
unsigned int channel; /**< the channel as on board and ADC module */
int adc_in_fp; /**< File Pointer to raw sysfs */
int value_bit; /**< 10 bits by default. Can be increased if board */
};

52
src/aio/aio.c
View File

@@ -29,8 +29,9 @@
#include "aio.h"
#include "mraa_internal.h"
#define DEFAULT_BITS 10
static int raw_bits;
static int sup_bits;
static mraa_result_t aio_get_valid_fp(mraa_aio_context dev)
{
@@ -92,6 +93,7 @@ mraa_aio_context mraa_aio_init(unsigned int aio_channel)
return NULL;
}
dev->channel = checked_pin;
dev->value_bit = DEFAULT_BITS;
//Open valid analog input file and get the pointer.
if (MRAA_SUCCESS != aio_get_valid_fp(dev)) {
@@ -99,7 +101,6 @@ mraa_aio_context mraa_aio_init(unsigned int aio_channel)
return NULL;
}
raw_bits = mraa_adc_raw_bits();
sup_bits = mraa_adc_supported_bits();
if (advance_func->aio_init_post != NULL) {
mraa_result_t ret = advance_func->aio_init_post(dev);
@@ -146,13 +147,13 @@ uint16_t mraa_aio_read(mraa_aio_context dev)
fprintf(stderr, "errno was set\n");
}
/* Adjust the raw analog input reading to supported resolution value*/
if (raw_bits != sup_bits) {
if (raw_bits > sup_bits) {
shifter_value = raw_bits - sup_bits;
if (dev->value_bit != raw_bits) {
/* Adjust the raw analog input reading to supported resolution value*/
if (raw_bits > dev->value_bit) {
shifter_value = raw_bits - dev->value_bit;
analog_value = analog_value >> shifter_value;
} else {
shifter_value = sup_bits - raw_bits;
shifter_value = dev->value_bit - raw_bits;
analog_value = analog_value << shifter_value;
}
}
@@ -173,3 +174,40 @@ mraa_result_t mraa_aio_close(mraa_aio_context dev)
return(MRAA_SUCCESS);
}
/** Set the bits value from read.
*
* @param dev the analog input context
* @param bits the bits the return from read should be i.e 10
*
* @return mraa result type
*/
mraa_result_t mraa_aio_set_bit(mraa_aio_context dev, int bits)
{
if (dev == NULL) {
fprintf(stderr, "AIO Device not valid\n");
return MRAA_ERROR_INVALID_RESOURCE;
}
if (bits < 1) {
fprintf(stderr, "AIO Device not valid\n");
// Error Message Here. find with grep fprintf
return MRAA_ERROR_INVALID_PARAMETER;
}
dev->value_bit = bits;
return MRAA_SUCCESS;
}
/**
* Gets the bit value mraa is shifting the analog read to.
* @param dev the analog input context
*
* @return bit value mraa is set return from the read function
*/
int mraa_aio_get_bit(mraa_aio_context dev)
{
if (dev == NULL) {
fprintf(stderr, "AIO Device not valid\n");
return 0;
}
return dev->value_bit;
}