DS1307 RTC

Device drive interface for the DS1307 real-time clock.

enum ds1307_sqw_mode_t
DS1307_SQW_MODE_0 = 0x00
OUT: 0.
DS1307_SQW_MODE_1000HZ = 0x10
SQW: 1kHz.
DS1307_SQW_MODE_4096HZ = 0x11
SQW: 4.096 kHz.
DS1307_SQW_MODE_8192HZ = 0x12
SQW: 8.192 kHz.
DS1307_SQW_MODE_32768HZ = 0x13
SQW: 32.768 kHz.
DS1307_SQW_MODE_1 = 0x80
OUT: 1.
int ds1307_init(ds1307_t * dev, const ds1307_params_t * params)

Initialize the given DS1307 device.

Parameters

dev:device descriptor of the targeted device
params:device configuration (i2c bus, address and bus clock)

Return values

  • 0 on success
  • < 0 if unable to speak to the device
int ds1307_set_time(const ds1307_t * dev, const struct tm * time)

Set RTC to a given time.

Parameters

dev:device descriptor of the targeted device
time:pointer to the struct holding the time to set.

Return values

  • 0 on success
  • < 0 if unable to speak to the device
int ds1307_get_time(const ds1307_t * dev, struct tm * time)

Get current RTC time.

Parameters

dev:device descriptor of the targeted device
time:pointer to the struct to write the time to.

Return values

  • 0 on success
  • < 0 if unable to speak to the device
int ds1307_halt(const ds1307_t * dev)

Halt clock.

Note

Can be reversed using ds1307.h::ds1307_set_time()

Parameters

dev:device descriptor of the targeted device

Return values

  • 0 on success
  • < 0 if unable to speak to the device
int ds1307_set_sqw_mode(const ds1307_t * dev, ds1307.h::ds1307_sqw_mode_t mode)

Set mode of square wave / output driver.

Note

To get the actual output of the driver, attach the pin via GPIO

Parameters

dev:device descriptor of the targeted device
mode:mode for the square wave / output driver

Return values

  • 0 on success
  • < 0 if unable to speak to the device
int ds1307_get_sqw_mode(const ds1307_t * dev)

Get current mode of square wave / output driver.

Note

To get the actual output of the driver, attach the pin via GPIO

Parameters

dev:device descriptor of the targeted device

Return values

  • current mode of the square wave / output driver (see ds1307_sqw_mode_t)
  • < 0 if unable to speak to the device
DS1307_I2C_ADDRESS

I2C address of DS1307 RTC. 

1
(0x68)
DS1307_I2C_MAX_CLK

Maximum I2C bus speed to use with the device. 

1
(I2C_SPEED_FAST)
DS1307_NVRAM_MAX_SIZE

Maximum size in byte of on-chip NVRAM. 

1
(56U)
struct ds1307_t

Device descriptor for DS1307 devices.

i2c.h::i2c_t i2c

I2C bus the device is connected to.

nvram.h::nvram_t nvram

on-chip NVRAM (see nvram.h)

struct ds1307_params_t

Set of configuration parameters for DS1307 devices.

i2c.h::i2c_t i2c

I2C bus the device is connected to.