arduino/esp8266
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Improve I2C waveforms

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This commit is contained in:
Ivan Grokhotkov 2015-05-29 20:40:18 +03:00
parent e8bdd50458
commit d862cdbb5a
1 changed files with 7 additions and 7 deletions
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14
cores/esp8266/core_esp8266_si2c.c
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@ -44,16 +44,16 @@ static unsigned char twi_sda, twi_scl;
void twi_setClock(unsigned int freq){
#if F_CPU == FCPU80
if(freq <= 100000) twi_dcount = 18;//about 100KHz
if(freq <= 100000) twi_dcount = 19;//about 100KHz
else if(freq <= 200000) twi_dcount = 8;//about 200KHz
else if(freq <= 300000) twi_dcount = 4;//about 300KHz
else if(freq <= 400000) twi_dcount = 2;//about 370KHz
else if(freq <= 300000) twi_dcount = 3;//about 300KHz
else if(freq <= 400000) twi_dcount = 1;//about 370KHz
else twi_dcount = 1;//about 450KHz
#else
if(freq <= 100000) twi_dcount = 32;//about 100KHz
else if(freq <= 200000) twi_dcount = 16;//about 200KHz
else if(freq <= 200000) twi_dcount = 14;//about 200KHz
else if(freq <= 300000) twi_dcount = 8;//about 300KHz
else if(freq <= 400000) twi_dcount = 4;//about 370KHz
else if(freq <= 400000) twi_dcount = 5;//about 370KHz
else twi_dcount = 2;//about 450KHz
#endif
}
@ -109,7 +109,7 @@ static bool twi_write_bit(bool bit) {
twi_delay(twi_dcount+1);
SCL_HIGH();
while (SCL_READ() == 0 && (i++) < TWI_CLOCK_STRETCH);// Clock stretching (up to 100us)
twi_delay(twi_dcount+1);
twi_delay(twi_dcount);
return true;
}
@ -117,7 +117,7 @@ static bool twi_read_bit(void) {
unsigned int i = 0;
SCL_LOW();
SDA_HIGH();
twi_delay(twi_dcount+1);
twi_delay(twi_dcount+2);
SCL_HIGH();
while (SCL_READ() == 0 && (i++) < TWI_CLOCK_STRETCH);// Clock stretching (up to 100us)
bool bit = SDA_READ();