mirror of https://github.com/SMFSW/cI2C
80 lines
3.6 KiB
Markdown
Executable File
80 lines
3.6 KiB
Markdown
Executable File
# cI2C
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Arduino Hardware I2C for AVR (plain c)
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Hardware I2C library for AVR MCUs (lib intended for I2C protocols development in c, for easier ports to other MCUs)
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## Library choice:
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* cI2C library implements I2C bus for AVR tagets (Uno, Nano, Mega...)
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* you may prefer this one when:
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* working on AVR targets
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* interrupts are not needed
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* WireWrapper implements I2C bus for every platform that includes Wire library
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* you would have to use this one when:
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* working on non-AVR targets
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* portability is needed (using Wire library)
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No refactoring is required when switching between **cI2C** & **WireWrapper** libs;
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Both libs share same Typedefs, Functions & Parameters.
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## Notes:
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* cI2C is written in plain c (intentionally)
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* cI2C does not use any interrupt (yet, but soon will have to)
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* cI2C is designed to act as bus Master (Slave mode will be considered in future releases)
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* cI2C is set to work on AVR targets only
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* for other targets, you may use **WireWrapper** instead (will be using Wire)
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## Usage:
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This library is intended to be able to work with multiple slaves connected on the same I2C bus.
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Thus, the I2C bus and Slaves are defined separately.
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* On one hand, I2C bus has to be initialised with appropriate speed:
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* use I2C_init(speed): speed can be choosen from I2C_SPEED enum for convenience, or passing an integer as parameter
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* On the other hand, Slave(s) have to be defined and initialised too:
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* use I2C_SLAVE typedef to declare slaves structs
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* use I2C_slave_init(pSlave, addr, regsize)
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* **pSlave** is a pointer to the slave struct to initialise
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* **addr** is the slave I2C address (don't shift addr, lib takes care of that)
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* **regsize** is the width of internal slave registers (to be choosen from I2C_INT_SIZE)
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* in case you need to use custom R/W procedures for a particular slave:
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* use I2C_slave_set_rw_func(pSlave, pFunc, rw)
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* **pSlave** is a pointer to the slave declaration to initialise
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* **pFunc** is a pointer to the Read or Write bypass function
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* **rw** can be choosen from I2C_RW enum (wr=0, rd=1)
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After all inits are done, the lib can basically be used this way:
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* I2C_read(pSlave, regaddr, pData, bytes)
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* **pSlave** is a pointer to the slave struct to read from
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* **regaddr** is the start address to read from
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* **pData** is a pointer to the place where datas read will be stored
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* **bytes** number of bytes to read from slave
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* returns true if read is ok, false otherwise
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* I2C_write(pSlave, regaddr, pData, bytes)
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* **pSlave** is a pointer to the slave struct to write to
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* **regaddr** is the start address to write to
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* **pData** is a pointer to the block of datas to write to slave
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* **bytes** number of bytes to write to slave
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* returns true if write is ok, false otherwise
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## Examples included:
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following examples should work with any I2C EEPROM/FRAM with address 0x50
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(yet function to get Chip ID are device dependant (and will probably only work on FUJITSU devices))
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* ci2c_master_write.ino: Write some bytes to FRAM and compare them with what's read afterwards
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* ci2c_master_read.ino: Read some bytes in FRAM
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* ci2c_advanced.ino: Redirecting slave write & read functions (to custom functions following typedef)
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Doxygen doc can be generated for the library using doxyfile
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## Links:
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Feel free to share your thoughts @ xgarmanboziax@gmail.com about:
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* issues encountered
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* optimisations
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* improvements & new functionalities
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**cI2C**
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- https://github.com/SMFSW/cI2C
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- https://bitbucket.org/SMFSW/ci2c
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**WireWrapper**
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- https://github.com/SMFSW/WireWrapper
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- https://bitbucket.org/SMFSW/wirewrapper
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