aide programmation température pic16f877

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bjr,
voila notre code... toute aide est la bienvenue!!!

/*
IIC BUS INTERFACE:

Code size for one read and one write to IIC device:

8 MHz clock : 110 instructions
4 MHz clock : 91 instructions
2 MHz clock : 82 instructions
500 kHz clock : 76 instructions

Use of macros are recommended. This module use
subroutines in one level. New macros may be
constructed in a similar way.

Delay syntax:
delay_4us_m3 : insert a 4 microseconds delay, but subtract the
time to execute 3 instruction cycles

1 instruction cycle = 4 clock cycles = 1 microsecond at 4 MHz
*/


#ifndef WRITE_sda

#define TEST_IIC

/* these should be user defined */

#define Clock_8MHz

#pragma bit scl_IIC @ PORTA.1
#pragma bit sda_IIC @ PORTA.0

#define WRITE_sda() TRISA = 0xFE
#define READ_sda() TRISA = 0xFF

#define IIC_address_RW_0 0xa2
#define IIC_address_RW_1 0xa3

char IIC_byte;
bit IIC_error, master_ack;

#endif

#ifdef Clock_8MHz
#define delay_(kn) { char x; x=kn; do x--; while (x>0); }
#define delay_4us_m1 delay_( 2)
#define delay_4us_m3 nop();nop();nop();nop();nop();
#define delay_4us_m6 nop(); nop();
#define delay_4us_m7 nop();
#define delay_4us_m8
#define delay_5us_m1 delay_( 3)
#define delay_5us_m2 delay_( 3)
#define delay_5us_m5 nop();nop();nop();nop();nop();
#define delay_5us_m7 nop();nop();nop();
#define delay_5us_m10
#define delay_0us_m1
#endif

#ifdef Clock_4MHz
#define delay_4us_m1 nop();nop();nop();
#define delay_4us_m3 nop();
#define delay_4us_m6
#define delay_4us_m7
#define delay_4us_m8
#define delay_5us_m1 nop();nop();nop();nop();
#define delay_5us_m2 nop();nop();nop();
#define delay_5us_m5
#define delay_5us_m7
#define delay_5us_m10
#define delay_0us_m1
#endif

#ifdef Clock_2MHz
#define delay_4us_m1 nop();
#define delay_4us_m3
#define delay_4us_m6
#define delay_4us_m7
#define delay_4us_m8
#define delay_5us_m1 nop();nop();
#define delay_5us_m2 nop();
#define delay_5us_m5
#define delay_5us_m7
#define delay_5us_m10
#define delay_0us_m1
#endif

#ifdef Clock_500kHz
#define delay_4us_m1
#define delay_4us_m3
#define delay_4us_m6
#define delay_4us_m7
#define delay_4us_m8
#define delay_5us_m1
#define delay_5us_m2
#define delay_5us_m5
#define delay_5us_m7
#define delay_5us_m10
#define delay_0us_m1
#endif


void startIICcomm( void)
/* assuming sda_IIC = 1 and scl_IIC = 1 */
{
WRITE_sda();
sda_IIC = 0;
delay_5us_m10
}


void stopIICcomm( void)
{
scl_IIC = 0;
WRITE_sda();
sda_IIC = 0;
delay_5us_m1
scl_IIC = 1;
delay_4us_m1
sda_IIC = 1;
delay_4us_m6
}


void readIICbus( void)
/* reads one byte from IIC slave device */
{
char counter;

scl_IIC = 0;
READ_sda();
counter = 8;
do {
scl_IIC = 0;
delay_5us_m1
scl_IIC = 1;
delay_4us_m7
Carry = sda_IIC;
IIC_byte = rl( IIC_byte);
} while ( -- counter > 0);

scl_IIC = 0;
WRITE_sda();
sda_IIC = master_ack;
delay_5us_m7
scl_IIC = 1;
delay_4us_m6
}


void sendIICbyte( char W)
/* writes one byte to IIC slave device */
{
char counter;

IIC_byte = W;
WRITE_sda();
counter = 8;

do {
IIC_byte = rl( IIC_byte);
scl_IIC = 0;
delay_5us_m5
sda_IIC = Carry;
delay_0us_m1 /* minimum 250 nanosec. */
scl_IIC = 1;
delay_4us_m3
} while ( -- counter > 0);

/* read ack. */

scl_IIC = 0;
READ_sda();
delay_5us_m2
scl_IIC = 1;
if ( sda_IIC)
IIC_error = 1;
delay_4us_m8
}


#define readByteFromIIC( address, variable) \
startIICcomm(); \
sendIICbyte( IIC_address_RW_0); \
sendIICbyte( address); \
stopIICcomm(); \
\
startIICcomm(); \
sendIICbyte( IIC_address_RW_1); \
\
/* more bytes to read .. \
master_ack = 0; \
readIICbus(); */ \
\
master_ack = 1; \
readIICbus(); \
stopIICcomm(); \
variable = IIC_byte


#define writeByteToIIC( address, IIC_data) \
startIICcomm(); \
sendIICbyte( IIC_address_RW_0); \
sendIICbyte( address); \
\
sendIICbyte( IIC_data); \
/* + more bytes to send \
sendIICbyte( .. ); */ \
\
stopIICcomm();

/* NOTE: EEPROM's require a delay between each
(block) write to the IIC device */


#ifdef TEST_IIC
void main( void)
{
char x;
//writeByteToIIC( 1, 100);

readByteFromIIC( 0x9A, x); /*C est Ici qu on voudrait pouvoir capter la temperature a partir
/*de l'adresse de la sonde sur le bus I2C


}
#endif

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