Freescale Semiconductor FRDM-FXS-MULTI 데이터 시트

다운로드
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MMA8652FC
Sensors
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Freescale Semiconductor, Inc.
6.5
System status and ID registers
6.5.1
0x0B: SYSMOD System Mode register
The System mode register indicates the current device operating mode. Applications using the Auto-SLEEP/WAKE mechanism 
should use the SYSMOD register to synchronize the application with the device operating mode transitions. The SYSMOD register 
also indicates: 
the status of the FIFO gate error 
and the number of samples since the gate error occurred.
6.5.2
0x0C: INT_SOURCE System Interrupt Status register
In the interrupt source register, the status of the various embedded features can be determined. 
The bits that are set (logic ‘1’) indicate which function has asserted an interrupt.
The bits that are cleared (logic ‘0’) indicate which function has not asserted (or has deasserted) an interrupt. 
INT_SOURCE register bits are set by a low-to-high transition, and are cleared by reading the appropriate interrupt source register. 
For example, the SRC_DRDY bit is cleared when the ZYXDR bit (STATUS register) is cleared, but the SRC_DRDY bit is not 
cleared by simply reading the STATUS register (0x00), but is cleared by reading all the X, Y, and Z MSB data. 
Table 23. 0x0B SYSMOD: System Mode register (Read-Only)
Back to Register Address Map
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
FGERR
FGT_4
FGT_3
FGT_2
FGT_1
FGT_0
SYSMOD1
SYSMOD0
Table 24. SYSMOD register
Bit(s)
Field
Description
7
FGERR
FIFO Gate Error
0 No FIFO Gate Error detected. (default)
1 FIFO Gate Error was detected.
Emptying the FIFO buffer clears the FGERR bit in the SYS_MOD register.
For more information about configuring the FIFO Gate function, se
.
6–2
FGT[4:0]
Number of ODR time units since FGERR was asserted
Reset when FGERR bit is cleared.
0_0000 (default) 
1–0
SYSMOD[1:0]
System Mode
00 STANDBY mode (default)
01 WAKE mode
10 SLEEP mode
Table 25. 0x0C INT_SOURCE: System Interrupt Status register (Read Only)
Back to Register Address Map
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SRC_ASLP
SRC_FIFO
SRC_TRANS
SRC_LNDPRT
SRC_PULSE
SRC_FF_MT
 —
SRC_DRDY