AN4602

Reading output data

Figure 4: DRDY flow

Summarizing the read from the DRDY pin:

1.

Read the DRDY pin

2.

If DRDY = 0, then go to step 1

3.

Read OUT_X_L

4.

Read OUT_X_H

5.

Read OUT_Y_L

6.

Read OUT_Y_H

7.

Read OUT_Z_L

8.

Read OUT_Z_H

9.

Data processing

10. Go to step 1

3.2.2

Using the STATUS_REG register

Directly polling the STATUS_REG register allows checking bit 7 (overrun). If bit 7 is set to

1, the reading rate is not adequate compared to the data production rate. If one or more

magnetometer samples have been overwritten by new data because of an excessively

slow reading rate, the ZYXOR bit of the STATUS_REG register is set to 1.

Reading from the STATUS_REG can be summarized as follows:

1.

Read STATUS_REG

2.

If STATUS_REG(3) = 0, then go to step 1

3.

If STATUS_REG(7) = 1, some data have been overwritten

4.

Read OUT_X_L

5.

Read OUT_X_H

6.

Read OUT_Y_L

7.

Read OUT_Y_H

8.

Read OUT_Z_L

9.

Read OUT_Z_H

10. Data processing

11. Go to step 1

DocID027014 Rev 1

13/23