HDPM01 Datasheet, PDF (15/19 Pages) List of Unclassifed Manufacturers – Integrated pressure sensor

HDPM01
DATA TRANSFER
A data transfer is started with a “START” condition and ended with a “STOP” condition. A “START”
condition is defined by a HIGH to LOW transition on the SDA line while SCL line is HIGH. A “STOP”
condition is defined by a LOW to HIGH transition on the SDA line while SCL line is HIGH. All data
transfer in I2C system is 8-bits long. Each byte has to be followed by an acknowledge bit. Each data
transfer involves a total of 9 clock cycles. Data is transferred starting with the most significant bit (MSB).
After a “START” condition, master device calls specific slave device, in our case, a HOPERF device
with a 7-bit device address “[0110xx0]”. To avoid potential address conflict, either by ICs from other
manufacturers or by other HOPERF devices on the same bus, a total of 4 different addresses can be
pre-programmed into HOPERF device by the factory. Following the 7-bit address, the 8th bit determines
the direction of data transfer: [1] for READ and [0] for WRITE. After being addressed, available
HOPERF device being called should respond by an “Acknowledge” signal, which is pulling SDA line
LOW.
In order to read sensor signal, master device should operate a WRITE action with a code of [xxxxxxx1]
into HOPERF device 8-bit internal register. Note that this action also serves as a “wake-up” call.
Tel: [phone] Fax: [phone] E-mail: [e-mail] http://www.hoperf.com
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