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[Modify] Turn off the scheduler when reading or writing ds18b20; Chan… #11

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[Modify] Turn off the scheduler when reading or writing ds18b20; Chan… #11

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8 changes: 6 additions & 2 deletions src/sensor_dallas_ds18b20.c
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Original file line number Diff line number Diff line change
Expand Up @@ -42,7 +42,7 @@ static void ds18b20_reset(rt_base_t pin)
static uint8_t ds18b20_connect(rt_base_t pin)
{
uint8_t retry = 0;
rt_pin_mode(pin, PIN_MODE_INPUT);
rt_pin_mode(pin, PIN_MODE_INPUT_PULLUP);

while (rt_pin_read(pin) && retry < 200)
{
Expand Down Expand Up @@ -75,7 +75,7 @@ static uint8_t ds18b20_read_bit(rt_base_t pin)
rt_pin_write(pin, PIN_LOW);
rt_hw_us_delay(2);
rt_pin_write(pin, PIN_HIGH);
rt_pin_mode(pin, PIN_MODE_INPUT);
rt_pin_mode(pin, PIN_MODE_INPUT_PULLUP);
/* maybe 12us, maybe 5us, whatever...I have no idea */
rt_hw_us_delay(5);

Expand All @@ -94,11 +94,13 @@ static uint8_t ds18b20_read_byte(rt_base_t pin)
uint8_t i, j, dat;
dat = 0;

rt_enter_critical();
for (i = 1; i <= 8; i++)
{
j = ds18b20_read_bit(pin);
dat = (j << 7) | (dat >> 1);
}
rt_exit_critical();

return dat;
}
Expand All @@ -109,6 +111,7 @@ static void ds18b20_write_byte(rt_base_t pin, uint8_t dat)
uint8_t testb;
rt_pin_mode(pin, PIN_MODE_OUTPUT);

rt_enter_critical();
for (j = 1; j <= 8; j++)
{
testb = dat & 0x01;
Expand All @@ -129,6 +132,7 @@ static void ds18b20_write_byte(rt_base_t pin, uint8_t dat)
rt_hw_us_delay(2);
}
}
rt_exit_critical();
}

void ds18b20_start(rt_base_t pin)
Expand Down