Finished MCP9808 driver.

This commit is contained in:
Pim van Pelt
2018-04-03 14:09:40 +02:00
parent 90003f705c
commit 50d59ae313
4 changed files with 61 additions and 19 deletions

View File

@ -22,6 +22,19 @@
// https://cdn-shop.adafruit.com/datasheets/MCP9808.pdf
// Private functions follow
static bool is_mcp9808(struct mgos_i2c *i2c, uint8_t i2caddr) {
uint16_t manufacturer_id, device_id;
manufacturer_id=mgos_i2c_read_reg_w(i2c, i2caddr, MGOS_MCP9808_REG_MANUF_ID);
device_id=mgos_i2c_read_reg_w(i2c, i2caddr, MGOS_MCP9808_REG_DEVICE_ID);
return ((manufacturer_id == 0x0054) && (device_id == 0x0400));
}
static void mgos_mcp9808_reset(struct mgos_mcp9808 *sensor) {
if (!sensor) return;
mgos_i2c_write_reg_w(sensor->i2c, sensor->i2caddr, MGOS_MCP9808_REG_CONFIG, 0x0);
}
// Private functions end
// Public functions follow
@ -30,21 +43,21 @@ struct mgos_mcp9808 *mgos_mcp9808_create(struct mgos_i2c *i2c, uint8_t i2caddr)
if (!i2c) return NULL;
if (!is_mcp9808(i2c, i2caddr)) {
LOG(LL_ERROR, ("Failed to create MCP9808 at I2C 0x%02x", i2caddr));
return NULL;
}
sensor=calloc(1, sizeof(struct mgos_mcp9808));
if (!sensor) return NULL;
sensor->i2caddr=i2caddr;
sensor->i2c=i2c;
sensor->last_read_time=0;
// Check for the right chip.
if (false) {
LOG(LL_INFO, ("MCP9808 created at I2C 0x%02x", i2caddr));
return sensor;
}
mgos_mcp9808_reset(sensor);
LOG(LL_ERROR, ("Failed to create MCP9808 at I2C 0x%02x", i2caddr));
free(sensor);
return NULL;
LOG(LL_INFO, ("MCP9808 created at I2C 0x%02x", i2caddr));
return sensor;
}
void mgos_mcp9808_destroy(struct mgos_mcp9808 **sensor) {
@ -65,6 +78,13 @@ bool mgos_mcp9808_read(struct mgos_mcp9808 *sensor) {
}
// Read out sensor data here
//
uint16_t temp_reg = mgos_i2c_read_reg_w(sensor->i2c, sensor->i2caddr, MGOS_MCP9808_REG_AMBIENT_TEMP);
float temperature = temp_reg & 0x0FFF;
temperature /= 16.0;
if (temp_reg & 0x1000) temperature -= 256;
sensor->temperature=temperature;
LOG(LL_DEBUG, ("temperature=%.2fC", sensor->temperature));
sensor->last_read_time=now;
return true;
@ -76,6 +96,15 @@ float mgos_mcp9808_getTemperature(struct mgos_mcp9808 *sensor) {
return sensor->temperature;
}
void mgos_mcp9808_enable(struct mgos_mcp9808 *sensor, bool enable) {
uint16_t conf_reg = mgos_i2c_read_reg_w(sensor->i2c, sensor->i2caddr, MGOS_MCP9808_REG_CONFIG);
if (enable)
conf_reg &= ~MGOS_MCP9808_REG_CONFIG_SHUTDOWN;
else
conf_reg |= MGOS_MCP9808_REG_CONFIG_SHUTDOWN;
mgos_i2c_write_reg_w(sensor->i2c, sensor->i2caddr, MGOS_MCP9808_REG_CONFIG, conf_reg);
}
bool mgos_mcp9808_i2c_init(void) {
return true;
}