Datasheet
Sensors
21 Freescale Semiconductor, Inc.
MMA7660FC
$09: Tap/Pulse Detection Register (Read/Write)
PDET
NOTE: If XDA = YDA = ZDA = 0, samples per second is 120 samples/second, and Auto-Wake/Sleep feature is enabled,
the tap interrupt will reset the sleep counter.
XDA
1: X-axis is disabled for tap detection
0: X-axis is enabled for tap detection
YDA
1: Y-axis is disabled for tap detection
0: Y-axis is enabled for tap detection
ZDA
1: Z-axis is disabled for tap detection
0: Z-axis is enabled for tap detection
$0A: PD: Tap/Pulse Debounce Count Register (Read/Write)
D7 D6 D5 D4 D3 D2 D1 D0
ZDA YDA XDA PDTH[4] PDTH[3] PDTH[2] PDTH[1] PDTH[0]
00000000
PDTH[4:0] DESCRIPTION
00000
Tap detection threshold is ±1 count
00001
00010 Tap detection threshold is ±2 counts
00011 Tap detection threshold is ±3 counts
... ... and so on up to...
11101 Tap detection threshold is ±29 counts
11110 Tap detection threshold is ±30 counts
11111 Tap detection threshold is ±31 counts
D7 D6 D5 D4 D3 D2 D1 D0
PD[7] PD[6] PD[5] PD[4] PD[3] PD[2] PD[1] PD[0]
00000000
PD[4:0] DESCRIPTION
00000000 The tap detection debounce filtering requires 2 adjacent tap detection tests to be the same to trigger a tap event and set the
Tap bit in the TILT (0x03) register, and optionally set an interrupt if PDINT is set in the INTSU (0x06) register. Tap detection
response time is nominally 0.52 ms.
00000001
00000010 Tap detection debounce filtering requires 3 adjacent tap detection tests to be the same to trigger a tap event and set the Tap
bit in the TILT (0x03) register, and optionally set an interrupt if PDINT is set in the INTSU (0x06) register. Tap detection
response time is nominally 0.78 ms.
00000011 Tap detection debounce filtering requires 4 adjacent tap detection tests to be the same to trigger a tap event and set the Tap
bit in the TILT (0x03) register, and optionally set an interrupt if PDINT is set in the INTSU (0x06) register. Tap detection
response time is nominally 1.04 ms.
... ... and so on up to...
11111101 Tap detection debounce filtering requires 254 adjacent tap detection tests to be the same to trigger a tap event and set the
Tap bit in the TILT (0x03) register, and optionally set an interrupt if PDINT is set in the INTSU (0x06) register. Tap detection
response time is nominally 66.04 ms.
11111110 Tap detection debounce filtering requires 255 adjacent tap detection tests to be the same to trigger a tap event and set the
Tap bit in the TILT (0x03) register, and optionally set an interrupt if PDINT is set in the INTSU (0x06) register. Tap detection
response time is nominally 66.3 ms.
11111111 Tap detection debounce filtering requires 256 adjacent tap detection tests to be the same to trigger a tap event and set the
Tap bit in the TILT (0x03) register, and optionally set an interrupt if PDINT is set in the INTSU (0x06) register. Tap detection
response time is nominally 66.56 ms.