87 lines
3.7 KiB
C
87 lines
3.7 KiB
C
/****************************************************************************
|
|
* Genesis Plus
|
|
* I2C Serial EEPROM (24Cxx) support
|
|
*
|
|
* Copyright (C) 2007-2013 Eke-Eke (Genesis Plus GX)
|
|
*
|
|
* Redistribution and use of this code or any derivative works are permitted
|
|
* provided that the following conditions are met:
|
|
*
|
|
* - Redistributions may not be sold, nor may they be used in a commercial
|
|
* product or activity.
|
|
*
|
|
* - Redistributions that are modified from the original source must include the
|
|
* complete source code, including the source code for all components used by a
|
|
* binary built from the modified sources. However, as a special exception, the
|
|
* source code distributed need not include anything that is normally distributed
|
|
* (in either source or binary form) with the major components (compiler, kernel,
|
|
* and so on) of the operating system on which the executable runs, unless that
|
|
* component itself accompanies the executable.
|
|
*
|
|
* - Redistributions must reproduce the above copyright notice, this list of
|
|
* conditions and the following disclaimer in the documentation and/or other
|
|
* materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************************/
|
|
|
|
#ifndef _EEPROM_I2C_H_
|
|
#define _EEPROM_I2C_H_
|
|
|
|
typedef struct
|
|
{
|
|
uint8 address_bits; /* number of bits needed to address memory: 7, 8 or 16 */
|
|
uint16 size_mask; /* depends on the max size of the memory (in bytes) */
|
|
uint16 pagewrite_mask; /* depends on the maximal number of bytes that can be written in a single write cycle */
|
|
uint32 sda_in_adr; /* 68000 memory address mapped to SDA_IN */
|
|
uint32 sda_out_adr; /* 68000 memory address mapped to SDA_OUT */
|
|
uint32 scl_adr; /* 68000 memory address mapped to SCL */
|
|
uint8 sda_in_bit; /* bit offset for SDA_IN */
|
|
uint8 sda_out_bit; /* bit offset for SDA_OUT */
|
|
uint8 scl_bit; /* bit offset for SCL */
|
|
} T_CONFIG_I2C;
|
|
|
|
typedef enum
|
|
{
|
|
STAND_BY = 0,
|
|
WAIT_STOP,
|
|
GET_SLAVE_ADR,
|
|
GET_WORD_ADR_7BITS,
|
|
GET_WORD_ADR_HIGH,
|
|
GET_WORD_ADR_LOW,
|
|
WRITE_DATA,
|
|
READ_DATA
|
|
} T_STATE_I2C;
|
|
|
|
typedef struct
|
|
{
|
|
uint8 sda; /* current /SDA line state */
|
|
uint8 scl; /* current /SCL line state */
|
|
uint8 old_sda; /* previous /SDA line state */
|
|
uint8 old_scl; /* previous /SCL line state */
|
|
uint8 cycles; /* current operation cycle number (0-9) */
|
|
uint8 rw; /* operation type (1:READ, 0:WRITE) */
|
|
uint16 slave_mask; /* device address (shifted by the memory address width)*/
|
|
uint16 word_address; /* memory address */
|
|
T_STATE_I2C state; /* current operation state */
|
|
T_CONFIG_I2C config; /* EEPROM characteristics for this game */
|
|
} T_EEPROM_I2C;
|
|
|
|
extern T_EEPROM_I2C eeprom_i2c;
|
|
|
|
/* Function prototypes */
|
|
extern void eeprom_i2c_init();
|
|
|
|
#endif
|