forked from mirrors/qmk_userspace
added ergodox
This commit is contained in:
Jack Humbert
parent
46e7fb2d3c
commit
35a81f5b8b
17 changed files with 1627 additions and 128 deletions
178
keyboard/ergodox/i2cmaster.h
Normal file
178
keyboard/ergodox/i2cmaster.h
Normal file
|
|
@ -0,0 +1,178 @@
|
|||
#ifndef _I2CMASTER_H
|
||||
#define _I2CMASTER_H 1
|
||||
/*************************************************************************
|
||||
* Title: C include file for the I2C master interface
|
||||
* (i2cmaster.S or twimaster.c)
|
||||
* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
|
||||
* File: $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $
|
||||
* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
|
||||
* Target: any AVR device
|
||||
* Usage: see Doxygen manual
|
||||
**************************************************************************/
|
||||
|
||||
#ifdef DOXYGEN
|
||||
/**
|
||||
@defgroup pfleury_ic2master I2C Master library
|
||||
@code #include <i2cmaster.h> @endcode
|
||||
|
||||
@brief I2C (TWI) Master Software Library
|
||||
|
||||
Basic routines for communicating with I2C slave devices. This single master
|
||||
implementation is limited to one bus master on the I2C bus.
|
||||
|
||||
This I2c library is implemented as a compact assembler software implementation of the I2C protocol
|
||||
which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c).
|
||||
Since the API for these two implementations is exactly the same, an application can be linked either against the
|
||||
software I2C implementation or the hardware I2C implementation.
|
||||
|
||||
Use 4.7k pull-up resistor on the SDA and SCL pin.
|
||||
|
||||
Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module
|
||||
i2cmaster.S to your target when using the software I2C implementation !
|
||||
|
||||
Adjust the CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion.
|
||||
|
||||
@note
|
||||
The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted
|
||||
to GNU assembler and AVR-GCC C call interface.
|
||||
Replaced the incorrect quarter period delays found in AVR300 with
|
||||
half period delays.
|
||||
|
||||
@author Peter Fleury pfleury@gmx.ch http://jump.to/fleury
|
||||
|
||||
@par API Usage Example
|
||||
The following code shows typical usage of this library, see example test_i2cmaster.c
|
||||
|
||||
@code
|
||||
|
||||
#include <i2cmaster.h>
|
||||
|
||||
|
||||
#define Dev24C02 0xA2 // device address of EEPROM 24C02, see datasheet
|
||||
|
||||
int main(void)
|
||||
{
|
||||
unsigned char ret;
|
||||
|
||||
i2c_init(); // initialize I2C library
|
||||
|
||||
// write 0x75 to EEPROM address 5 (Byte Write)
|
||||
i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
|
||||
i2c_write(0x05); // write address = 5
|
||||
i2c_write(0x75); // write value 0x75 to EEPROM
|
||||
i2c_stop(); // set stop conditon = release bus
|
||||
|
||||
|
||||
// read previously written value back from EEPROM address 5
|
||||
i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
|
||||
|
||||
i2c_write(0x05); // write address = 5
|
||||
i2c_rep_start(Dev24C02+I2C_READ); // set device address and read mode
|
||||
|
||||
ret = i2c_readNak(); // read one byte from EEPROM
|
||||
i2c_stop();
|
||||
|
||||
for(;;);
|
||||
}
|
||||
@endcode
|
||||
|
||||
*/
|
||||
#endif /* DOXYGEN */
|
||||
|
||||
/**@{*/
|
||||
|
||||
#if (__GNUC__ * 100 + __GNUC_MINOR__) < 304
|
||||
#error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !"
|
||||
#endif
|
||||
|
||||
#include <avr/io.h>
|
||||
|
||||
/** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */
|
||||
#define I2C_READ 1
|
||||
|
||||
/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */
|
||||
#define I2C_WRITE 0
|
||||
|
||||
|
||||
/**
|
||||
@brief initialize the I2C master interace. Need to be called only once
|
||||
@param void
|
||||
@return none
|
||||
*/
|
||||
extern void i2c_init(void);
|
||||
|
||||
|
||||
/**
|
||||
@brief Terminates the data transfer and releases the I2C bus
|
||||
@param void
|
||||
@return none
|
||||
*/
|
||||
extern void i2c_stop(void);
|
||||
|
||||
|
||||
/**
|
||||
@brief Issues a start condition and sends address and transfer direction
|
||||
|
||||
@param addr address and transfer direction of I2C device
|
||||
@retval 0 device accessible
|
||||
@retval 1 failed to access device
|
||||
*/
|
||||
extern unsigned char i2c_start(unsigned char addr);
|
||||
|
||||
|
||||
/**
|
||||
@brief Issues a repeated start condition and sends address and transfer direction
|
||||
|
||||
@param addr address and transfer direction of I2C device
|
||||
@retval 0 device accessible
|
||||
@retval 1 failed to access device
|
||||
*/
|
||||
extern unsigned char i2c_rep_start(unsigned char addr);
|
||||
|
||||
|
||||
/**
|
||||
@brief Issues a start condition and sends address and transfer direction
|
||||
|
||||
If device is busy, use ack polling to wait until device ready
|
||||
@param addr address and transfer direction of I2C device
|
||||
@return none
|
||||
*/
|
||||
extern void i2c_start_wait(unsigned char addr);
|
||||
|
||||
|
||||
/**
|
||||
@brief Send one byte to I2C device
|
||||
@param data byte to be transfered
|
||||
@retval 0 write successful
|
||||
@retval 1 write failed
|
||||
*/
|
||||
extern unsigned char i2c_write(unsigned char data);
|
||||
|
||||
|
||||
/**
|
||||
@brief read one byte from the I2C device, request more data from device
|
||||
@return byte read from I2C device
|
||||
*/
|
||||
extern unsigned char i2c_readAck(void);
|
||||
|
||||
/**
|
||||
@brief read one byte from the I2C device, read is followed by a stop condition
|
||||
@return byte read from I2C device
|
||||
*/
|
||||
extern unsigned char i2c_readNak(void);
|
||||
|
||||
/**
|
||||
@brief read one byte from the I2C device
|
||||
|
||||
Implemented as a macro, which calls either i2c_readAck or i2c_readNak
|
||||
|
||||
@param ack 1 send ack, request more data from device<br>
|
||||
0 send nak, read is followed by a stop condition
|
||||
@return byte read from I2C device
|
||||
*/
|
||||
extern unsigned char i2c_read(unsigned char ack);
|
||||
#define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();
|
||||
|
||||
|
||||
/**@}*/
|
||||
#endif
|
||||
Loading…
Add table
Add a link
Reference in a new issue