I3G4250D Datasheet, PDF (19/43 Pages) STMicroelectronics – 3-axis digital output gyroscope

I3G4250D
Main digital blocks
The read from FIFO may be executed either in synchronous or asynchronous mode. For
correct data acquisition, the following points must be respected:
1. If reading is synchronous, all data should be acquired within one ODR cycle
2. If reading is asynchronous, an appropriate FIFO access sequence must be applied:
a) Single read from register 28h
b) Multi-read: sequentially reading 2Ah, 2Bh, 2Ch, 2Dh, 28h, 29h
c) This procedure must be repeated for each dataset (X/Y/Z) in the FIFO:
– FSS times, if FSS 31
– (FSS + 1) times, if (FSS = 31) & (OVR =1)
Figure 10 illustrates the correct sequence with a flow diagram:
Figure 10. FIFO access sequence in asynchronous mode
If the above sequence is not followed, the acquisition from FIFO may lead to corrupted data.
DocID027628 Rev 2
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