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add "api reference" (i2c rtc sd_card)
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watson8544
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I2C API
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********
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-----------------------------
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Description
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------------
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Both master and slave modes are supported
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Master and slave modes can be used at the same time, on different I2C interfaces
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-----------------------------
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Function
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---------
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machine.I2C(id, mode, speed, sda, scl, slave_addr, slave_bufflen, slave_rolen, slave_busy)
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Create the I2C instance object
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| **Parament:**
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| **id:** The hardware I2C peripheral ID; 0 or 1 can be used. Default: 0
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| **mode:** I2C interface mode; master or slave. Use the constants **machine.I2C.MASTER** or **machine.I2C.SLAVE** Default: master
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| **speed:** I2C clock frequency in **Hz**. Default: 100000
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| **sda:** I2C **sda** pin; can be given as integer gpio number or Pin object
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| **scl:** I2C **scl** pin; can be given as integer gpio number or Pin object
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| **slave_addr:** I2C slave address to be assigned to this i2c interface. Only used if SLAVE mode is selected
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| **slave_bufflen:** Size of slave buffer used for master<->slave comunication in bytes
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| **slave_rolen:** Size of **read-only** area at the end of the slave buffer in bytes
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| **slave_busy:** Only used if **SLAVE** mode is selected
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| *Note: Only sda and scl are required, all the others are optional and will be set to the default values if not given*
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init(args)
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>>>>>>>>>>>>>>>>>
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| **Description:**
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| Reinitialize an existing I2C object
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| **Parament:**
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| **The arguments are the same as for creating a new i2c instance object**
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scan()
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>>>>>>>>>>>>>>>>>
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| **Description:**
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| Scan for i2c devices on I2C bus. Does not scan reserved 7-bit addresses: **0x00-0x07** & **0x78-0x7F**
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| *Note: can only be used in master mode*
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| **Parament:**
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| **None**
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| **Return:**
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| Returns the list of detected addresses
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readfrom(addr, nbytes)
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Read **nbytes** bytes from i2c device with address **addr**
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| *Note: can only be used in master mode*
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| **Parament:**
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| **None:**
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| **Return:**
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| Return bytearray of read bytes
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writeto(addr, buf [,stop=True])
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Write the content of the buffer object **buf** to the i2c device with address **adr**
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| *Note: can only be used in master mode*
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| **Parament:**
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| *Note: If optional stop argument is set to False, the stop signal is not issued*
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readfrom_into(addr, buf)
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Read from i2c device with address **addr** into buffer object **buf**
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| *Note: can only be used in master mode*
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| **Parament:**
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| *Note: Size of buf bytes are read*
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---------------------
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Usage
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------
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.. code:: python
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from machine import I2C
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i2c = I2C(freq=400000, sda=21, scl=22)
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# create I2C peripheral at frequency of 400kHz
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# depending on the port, extra parameters may be required
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# to select the peripheral and/or pins to use
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i2c.scan() # scan for slaves, returning a list of 7-bit addresses
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i2c.writeto(42, b'123') # write 3 bytes to slave with 7-bit address 42
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i2c.readfrom(42, 4) # read 4 bytes from slave with 7-bit address 42
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i2c.readfrom_mem(42, 8, 3) # read 3 bytes from memory of slave 42,
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# starting at memory-address 8 in the slave
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i2c.writeto_mem(42, 2, b'\x10') # write 1 byte to memory of slave 42
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# starting at address 2 in the slave
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@@ -0,0 +1,107 @@
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RTC API
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********
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-----------------------------
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Description
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------------
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The content of the RTC memory is preserved during the deep sleep.
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Up to 64 32-bit integers can be saved in RTC memory.
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One string of up to 2048 characters can be saved in RTC memory.
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The string can be, for example, json string containing the parameters which has to be restored after deep sleep wake-up.
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Integers and string saved in RTC memory are protected by 16-bit CRC
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-----------------------------
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Function
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---------
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machine.RTC()
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Create the RTC instance object
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init(date)
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Set the system time and date
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| **Parament:**
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| **date:** it's a tuple containing the time and date information
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| *Note: the tuple is equal to (year, month, day [,hour [,minute [, second ]]])*
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now()
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>>>>>>>>>>>>>>>>>
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| **Description:**
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| get the current time
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| **Parament:**
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| **None**
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| **Return:**
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| Return the current time as tuple: `(year, month, day, hour, minute, second)`
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ntp_sync(server [,update_period] [,tz])
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>>>>>>>>>>>>>>>>>
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| **Description:**
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| Write bytes from buffer object buf to the RTC device
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| **Parament:**
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| **server :** the NTP server domain name or IP, for example "pool.ntp.org"
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| **update_period:** optional, time update interval in seconds; default: 3600
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| **tz:** optional, time zone string; default: the one set in menuconfig
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| **Return:**
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| Returns `True` on success, `False` ion error
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| **Example:**
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.. code:: python
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import machine
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import utime
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rtc = machine.RTC()
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rtc.ntp_sync(server="hr.pool.ntp.org", tz="CET-1CEST")
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synced()
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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
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| **Description:**
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| Sync the system time from NTP server
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| **Parament:**
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| **None:**
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| **Return:**
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| Return `True` if the system time was synced from NTP server, `False` if not
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---------------------
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Usage
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------
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.. code:: python
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import machine
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import utime
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rtc = machine.RTC()
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rtc.ntp_sync(server="hr.pool.ntp.org", tz="CET-1CEST")
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rtc.synced()
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True
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utime.gmtime()
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(2018, 1, 29, 16, 3, 18, 2, 29)
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utime.localtime()
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(2018, 1, 29, 17, 3, 30, 2, 29)
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