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drivers: sensor: HS300x DF Command Update

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By default, the sensor should be factory-programmed to operate
in Sleep Mode. A Measurement Request (MR) command is required
to exit the sensor from its sleep state. An MR command should
consist of the 7-bit address followed by an eighth bit set to
0 (write). However, many I2C controllers cannot generate merely
the address byte with no data. To overcome this limitation the
MR command should be followed by a dummy byte (zero value).

Signed-off-by: Ioannis Karachalios <ioannis.karachalios.px@renesas.com>
This commit is contained in:
Ioannis Karachalios 2024-02-27 10:51:05 +02:00 committed by Fabio Baltieri
parent eda7dd1460
commit 0abba58953
1 changed files with 8 additions and 3 deletions
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11
drivers/sensor/hs300x/hs300x.c
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@ -58,6 +58,7 @@ static int hs300x_sample_fetch(const struct device *dev, enum sensor_channel cha
struct hs300x_data *data = dev->data;
const struct hs300x_config *cfg = dev->config;
int rc;
uint8_t df_dummy = 0x0;
if (chan != SENSOR_CHAN_ALL && chan != SENSOR_CHAN_AMBIENT_TEMP &&
chan != SENSOR_CHAN_HUMIDITY) {
@ -65,10 +66,14 @@ static int hs300x_sample_fetch(const struct device *dev, enum sensor_channel cha
}
/*
* Initiate a measurement simply by sending 7-bit address followed
* by an eighth bit set to 0 (write) and NO data.
* By default, the sensor should be factory-programmed to operate in Sleep Mode.
* A Measurement Request (MR) command is required to exit the sensor
* from its sleep state. An MR command should consist of the 7-bit address followed
* by an eighth bit set to 0 (write). However, many I2C controllers cannot generate
* merely the address byte with no data. To overcome this limitation the MR command
* should be followed by a dummy byte (zero value).
*/
rc = i2c_write_dt(&cfg->bus, NULL, 0);
rc = i2c_write_dt(&cfg->bus, (const uint8_t *)&df_dummy, 1);
if (rc < 0) {
LOG_ERR("Failed to start measurement.");
return rc;