mirror of
https://github.com/ekeeke/Genesis-Plus-GX.git
synced 2024-11-05 10:25:07 +01:00
73 lines
2.8 KiB
C
73 lines
2.8 KiB
C
/****************************************************************************
|
|
* Genesis Plus
|
|
* Microwire Serial EEPROM (93C46 only) support
|
|
*
|
|
* Copyright (C) 2011 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_93C_H_
|
|
#define _EEPROM_93C_H_
|
|
|
|
typedef enum
|
|
{
|
|
WAIT_STANDBY,
|
|
WAIT_START,
|
|
GET_OPCODE,
|
|
WRITE_WORD,
|
|
READ_WORD
|
|
} T_STATE_93C;
|
|
|
|
typedef struct
|
|
{
|
|
uint8 enabled; /* 1: chip enabled */
|
|
uint8 cs; /* CHIP SELECT line state */
|
|
uint8 clk; /* CLK line state */
|
|
uint8 data; /* DATA OUT line state */
|
|
uint8 cycles; /* current operation cycle */
|
|
uint8 we; /* 1: write enabled */
|
|
uint8 opcode; /* 8-bit opcode + address */
|
|
uint16 buffer; /* 16-bit data buffer */
|
|
T_STATE_93C state; /* current operation state */
|
|
} T_EEPROM_93C;
|
|
|
|
/* global variables */
|
|
extern T_EEPROM_93C eeprom_93c;
|
|
|
|
/* Function prototypes */
|
|
extern void eeprom_93c_init();
|
|
extern void eeprom_93c_write(unsigned char data);
|
|
extern unsigned char eeprom_93c_read(void);
|
|
|
|
#endif
|