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Hi,
I am looking for I2C access in UBL and I need some basic functions like I2C_Write() or I2C_Read().
I have checked many I2C releases, but I only found a I2C_Init().
I am using the DM355, but helpfull would also be the basic functions for any other TI ARM Processor, like the OMAP. As far as I know the I2C modules are pretty much the same on every TI ARM processor.
Thank you for your support,
Sebastian
I'm not aware of any UBL examples, but I've attached some basic I2C test code you can use as an example
/*
* Copyright 2007 by Spectrum Digital Incorporated.
* All rights reserved. Property of Spectrum Digital Incorporated.
*/
/*
* I2C implementation
*
*/
#include "evmdm365_i2c.h"
#include "evmdm365_eeprom.h"
Int32 i2c_timeout = 0x10000;
/* ------------------------------------------------------------------------ *
* *
* _I2C_init( ) *
* *
* Enable and initalize the I2C module *
* The I2C clk is set to run at 100 KHz *
* *
* ------------------------------------------------------------------------ */
Int16 EVMDM365_I2C_init( )
{
I2C_ICMDR = 0; // Reset I2C
I2C_ICPSC = 11; // Config prescaler for 2MHz
I2C_ICCLKL = 5; // Config clk LOW for 100kHz
I2C_ICCLKH = 5; // Config clk HIGH for 100kHz
I2C_ICMDR |= ICMDR_IRS; // Release I2C from reset
return 0;
}
/* ------------------------------------------------------------------------ *
* *
* _I2C_close( ) *
* *
* ------------------------------------------------------------------------ */
Int16 EVMDM365_I2C_close( )
{
I2C_ICMDR = 0; // Reset I2C
return 0;
}
/* ------------------------------------------------------------------------ *
* *
* _I2C_reset( ) *
* *
* ------------------------------------------------------------------------ */
Int16 EVMDM365_I2C_reset( )
{
EVMDM365_I2C_close( );
EVMDM365_I2C_init( );
return 0;
}
/* ------------------------------------------------------------------------ *
* *
* _I2C_write( i2c_addr, data, len ) *
* *
* I2C write in Master mode *
* *
* i2c_addr <- I2C slave address *
* data <- I2C data ptr *
* len <- # of bytes to write *
* *
* ------------------------------------------------------------------------ */
Int16 EVMDM365_I2C_write( Uint16 i2c_addr, Uint8* data, Uint16 len )
{
Int32 timeout, i;
I2C_ICCNT = len; // Set length
I2C_ICSAR = i2c_addr; // Set I2C slave address
I2C_ICMDR = ICMDR_STT // Set for Master Write
| ICMDR_TRX
| ICMDR_MST
| ICMDR_IRS
| ICMDR_FREE;
_wait( 10 ); // Short delay
for ( i = 0 ; i < len ; i++ )
{
I2C_ICDXR = data[i]; // Write
timeout = i2c_timeout;
do
{
if ( timeout-- < 0 )
{
EVMDM365_I2C_reset( );
return -1;
}
} while ( ( I2C_ICSTR & ICSTR_ICXRDY ) == 0 );// Wait for Tx Ready
}
I2C_ICMDR |= ICMDR_STP; // Generate STOP
while(I2C_ICSTR & 0x1000);
EVMDM365_waitusec(30);
return 0;
}
/* ------------------------------------------------------------------------ *
* *
* _I2C_read( i2c_addr, data, len ) *
* *
* I2C read in Master mode *
* *
* i2c_addr <- I2C slave address *
* data <- I2C data ptr *
* len <- # of bytes to write *
* *
* Returns: 0: PASS *
* -1: FAIL Timeout *
* *
* ------------------------------------------------------------------------ */
Int16 EVMDM365_I2C_read( Uint16 i2c_addr, Uint8* data, Uint16 len )
{
Int32 timeout, i;
I2C_ICCNT = len; // Set length
I2C_ICSAR = i2c_addr; // Set I2C slave address
I2C_ICMDR = ICMDR_STT // Set for Master Read
| ICMDR_MST
| ICMDR_IRS
| ICMDR_FREE;
_wait( 10 ); // Short delay
for ( i = 0 ; i < len ; i++ )
{
timeout = i2c_timeout;
/* Wait for Rx Ready */
do
{
if ( timeout-- < 0 )
{
EVMDM365_I2C_reset( );
return -1;
}
} while ( ( I2C_ICSTR & ICSTR_ICRRDY ) == 0 );// Wait for Rx Ready
data[i] = I2C_ICDRR; // Read
}
I2C_ICMDR |= ICMDR_STP; // Generate STOP
while(I2C_ICSTR & 0x1000);
EVMDM365_waitusec(30);
return 0;
}
/* ------------------------------------------------------------------------ *
* *
* _I2C_read_variable( i2c_addr, data, len ) *
* *
* I2C read in Master mode *
* *
* i2c_addr <- I2C slave address *
* data <- I2C data ptr *
* len <- # of bytes to write *
* *
* ------------------------------------------------------------------------ */
Int16 EVMDM365_I2C_read_variable( Uint16 i2c_addr, Uint8* data, Uint16 len )
{
Int32 timeout, i;
I2C_ICCNT = len; // Set length
I2C_ICSAR = i2c_addr; // Set I2C slave address
I2C_ICMDR = ICMDR_STT // Set for Master Read
| ICMDR_MST
| ICMDR_IRS
| ICMDR_FREE;
_wait( 10 ); // Short delay
for ( i = 0 ; i < len ; i++ )
{
if ( i == 1 )
{
len = data[0];
I2C_ICCNT = len; // Set length
}
timeout = i2c_timeout;
do
{
if ( timeout-- < 0 )
{
EVMDM365_I2C_reset( );
return -1;
}
} while ( ( I2C_ICSTR & ICSTR_ICRRDY ) == 0 );// Wait for Rx Ready
data[i] = I2C_ICDRR; // Read
}
I2C_ICMDR |= ICMDR_STP; // Generate STOP
return 0;
}
Hi Marcus!
The basic I2C functions you sent me work perfectly. I just had to adjust the timing parameter in the I2C_Init() to a higher prescaler clocking rate.
Thank you for your support!
Sebastian