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/* This file has been prepared for Doxygen automatic documentation generation.*/
/*! \file *********************************************************************
*
* \brief EDID Injector firmware
*
* \author
* Wolfgang 'datenwolf' Draxinger
* Support email: projects+edid_injector@datenwolf.net
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form 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.
*
* 3. The name of ATMEL may not be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY ATMEL "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 EXPRESSLY AND
* SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
*****************************************************************************/
#include "avr_compiler.h"
#include <string.h>
#include "eeprom_driver.h"
#include "twi_master_driver.h"
#include "twi_slave_driver.h"
/*! BAUDRATE 100kHz and Baudrate Register Settings */
#define BAUDRATE 100000
#define TWI_BAUDSETTING TWI_BAUD(F_CPU, BAUDRATE)
#define EDID_SLAVE_ADDRESS 0xA0
/* TWIC is on the display side */
TWI_t * const twiDisplay = &TWIC;
TWI_Master_t twimDisplay; /*!< TWI master module. Used for talking with display */
/*! TWIC Master Interrupt vector. */
ISR(TWIC_TWIM_vect)
{
TWI_MasterInterruptHandler(&twimDisplay);
}
/* TWIE is on the host side */
TWI_t * const twiHost = &TWIE;
TWI_Slave_t twisHost; /*!< TWI slave module. Used for talking with host */
/*! TWIC Slave Interrupt vector. */
ISR(TWIE_TWIS_vect)
{
TWI_SlaveInterruptHandler(&twisHost);
}
void TWIC_SlaveProcessData(void)
{
}
void edid_initHostTWI(void)
{
/* Initialize TWI slave. */
TWI_SlaveInitializeDriver(&twisHost, twiHost, TWIC_SlaveProcessData);
TWI_SlaveInitializeModule(&twisHost,
EDID_SLAVE_ADDRESS,
TWI_SLAVE_INTLVL_MED_gc );
}
void edid_initDisplayTWI(void)
{
/* Initialize TWI master. */
TWI_MasterInit(&twimDisplay,
twiDisplay,
TWI_MASTER_INTLVL_LO_gc,
TWI_BAUDSETTING);
/* Enable internal pull-up on PC0, PC1. */
/* If you don't have external pullups enable this */
#if 0
/* Configure several PINxCTRL registers at the same time */
PORTCFG.MPCMASK = 0x03;
/* Enable pull-up to get a defined level on the switches */
PORTC.PIN0CTRL = (PORTC.PIN0CTRL & ~PORT_OPC_gm) | PORT_OPC_PULLUP_gc;
#endif
}
uint8_t edid_genChecksum(uint8_t *ediddata)
{
uint8_t bytessum = 0;
for(size_t i = 0; i < 127; i++) {
bytessum += ediddata[i];
}
return 0xff - bytessum;
}
void edid_readFromDisplayToEEPROM(void)
{
uint8_t displayedid[128];
memset(displayedid, 0, sizeof(displayedid));
/* read 128 EDID bytes from display */
/* set EDID Extension Block count / flags to zero */
/* recalculate checksum */
displayedid[127] = edid_genChecksum(displayedid);
/* write EDID information to EEPROM */
}
int main(void)
{
edid_initHostTWI();
edid_initDisplayTWI();
sei();
#if 0
TWI_MasterWriteRead(&twiMaster,
SLAVE_ADDRESS,
&sendBuffer[BufPos],
1,
1);
while (twiMaster.status != TWIM_STATUS_READY) {
/* Wait until transaction is complete. */
}
#endif
}
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