
4.5
4.5.1
4.5.1.1
PSI5 Transmission Modes
Normal Mode
Asynchronous Mode
The device can be programmed to respond in asynchronous mode with the following settings:
? TRANS_MD[1:0] = ‘00’ (“Normal Mode”)
? ASYNC = ‘1’ in the DEVCFG6 Register
? TIMESLOTA[9:0] = 0x000 in the DEVCFG3 and DEVCFG4 registers
In asynchronous mode, the device transmits data at a fixed rate (t ASYNC ) and will not respond to normal sync pulses. However,
during initialization phase 1, sync pulses are monitored to decode the Programming Mode Entry Command and allow entry into
Programming Mode if the LOCK_U bit is not set.
4.5.1.2
Simultaneous Sampling Mode
The device can be programmed to respond in Simultaneous Sampling Mode by setting the TRANS_MD[1:0] bits to “Normal
Mode”, and by programming the LATENCY bit to “Simultaneous Sampling Mode”.
In Simultaneous Sampling Mode, the most recent interpolated acceleration data sample is latched at t TRIG (rising edge of Sync
Pulse) and transmitted starting at the time programmed in TIMESLOTA[9:0], relative to t TRIG .
≤ t LAT_INTERP
t TIMESLOTA
Figure 35. Simultaneous Sampling Mode
MMA52xxKW
Sensors
Freescale Semiconductor, Inc.
43