MMA7456L 데이터 시트보기 (PDF) - Freescale Semiconductor
부품명
상세내역
일치하는 목록
MMA7456L Datasheet PDF : 36 Pages
| |||
PULSE DETECTION
There are two interrupt pins available for detection of level and pulse conditions. The pulse detection has several timing windows
associated with it. A single pulse and a double pulse can be detected. Also freefall can be detected. The interrupt pins can be
assigned to detect the first pulse on one interrupt and the second pulse on the other interrupt. This is explained on
Page page 15, under the Assigning, Clearing & Detecting Interrupts section.
By default all three axes are enabled and the detection range is 8g only. X and/or Y and/or Z can be disabled. There is a choice
between doing a detection for Motion detection vs. doing a detection for Freefall.
$18: Control 1 (Read/Write): Disable X, Y or Z for pulse detection
This allows the user to define how many axes to use for detection. All axes are enabled by default. To disable write 1
XDA: Disable X
YDA: Disable Y
ZDA: Disable Z.
D7
DFBW
0
D6
THOPT
0
D5
ZDA
0
D4
YDA
0
D3
XDA
0
D2
INTREG[1]
0
D1
INTREG[0]
0
D0
INTPIN
0
Reg $18
Function
Default
$19: Control 2 (Read/Write): Motion Detection (OR condition) or Freefall Detection (AND condition)
PDPL
0: Pulse detection polarity is positive and detecting condition is OR 3 axes.
1: Pulse detection polarity is negative and detecting condition is AND 3 axes.
D7
D6
D5
D4
D3
D2
D1
D0
--
--
--
--
--
DRVO
PDPL
LDPL
0
0
0
0
0
0
0
0
Reg $19
Function
Default
CASE 1: Single Pulse Motion Detection: X or Y or Z > Pulse Threshold for Time < Pulse Duration
For motion detection with single pulse the device must be in pulse mode. PDPL in Register $19 =0 for “OR” motion condition.
The Pulse threshold must be set in Register $1B and the pulse duration time window must also be set using Register $1C. The
pulse must be detected before the time window closes for the interrupt to trigger.
$1B: Pulse Detection Threshold Limit Value (Read/Write)
D7
D6
D5
D4
D3
PDTH[7]
PDTH[6]
PDTH[5]
PDTH[4]
PDTH[3]
0
0
0
0
0
D2
PDTH[2]
0
D1
PDTH[1]
0
D0
PDTH[0]
0
Reg $1B
Function
Default
$1C: Pulse Duration Value (Read/Write)
D7
D6
D5
PD[7]
PD[6]
PD[5]
0
0
0
D4
PD[4]
0
D3
PD[3]
0
D2
PD[2]
0
D1
PD[1]
0
D0
PD[0]
1
Reg $1C
Function
Default
MMA7456L
12
Sensors
Freescale Semiconductor
Share Link: 