Normal Operation (Polling) - Honeywell IPT User Manual

3.1.2 Normal Operation (Polling)

3.1.2.1 Pressure Channel
After initializing the Mode register per section 3.1.1.2, a new 24-bit pressure value will be available in ~
5.26 ms (1 ms settle time + 4.26 ms conversion).
The pressure conversion remains in the data register and DOUT/ RDY remains active (low) until the
data is read or another conversion is performed.
The process of reading the conversion and reconfiguring the ADC for single conversion mode requires
repeated cycling through the following steps:
1. Wait > 5.26 ms for the conversion to complete, and/or monitor the status of the
2. Send 0x58 to the Communications register to indicate a subsequent read of the 24-bit
3. Send 24 clock cycles to read the 24-bit Data register.
4. Send 0x08 to the Communications register to indicate a subsequent write to the 16-bit
5. Send 0x3001 to the Mode register to place the ADC into a single conversion mode and
6. Repeat
3.1.2.1 Temperature Channel
After initializing the Mode register per section 3.1.1.1, a new 16-bit temperature value will be available
in ~ 100 ms. (As temperature is generally a more slowly changing input than pressure, and has a
modest impact on the pressure output, this conversion rate should be adequate for most applications.)
The temperature conversion remains in the data register and DOUT/ RDY remains active (low) until
the data is read or another conversion is performed.
The process of reading the conversion and reconfiguring the ADC for single conversion mode requires
repeated cycling through the following steps:
1. Wait 100 ms for the conversion to complete and/or monitor the status of the
2. Send 0x38 to the Communications register to indicate a subsequent read of the 16-bit
3. Send 16 clock cycles to read the 16-bit Data register.
4. Send 0x10 to the Communications register to indicate a subsequent write to the 8-bit
5. Send 0x80 to the Mode register to place the ADC into a single conversion mode.
6. Repeat
DOUT/ RDY line.
Data register.
Mode register.
set the update rate to 470 Hz.
DOUT/ RDY line.
Data register.
Mode register.
10