sca3060 VTI Hamlin, sca3060 Datasheet - Page 10

• Manufacturer Part Number: sca3060
• Description: 3-axis Accelerometer
• Manufacturer: VTI Hamlin

2.4.2.1
2.4.3
2.5 Interrupt function (INT-pin)
2.5.1
2.6 Clock
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Examples
Usage
Overflow condition
Overflow is detected from data ring buffer in the same way as from the output registers. See
section 2.2.3.1 for details.
A simple example of output ring buffer usage:
In the next
data with 8 bit resolution and reduced data rate (only every second sample is stored into output
ring buffer). In
is ¾ full:
The Motion Detector will generate an interrupt to INT-pin when the corresponding function is
enabled and the interrupt condition is met. The SCA3060's ring buffer will generate an interrupt
when interrupt functionality has been enabled. Setting BUF_F_EN bit in INT_MASK register "1"
results in interrupt when the register is 75% full. Setting BUF_H_EN bit in INT_MASK register "1"
results in interrupt when the register is 50% full.
Setting INT_ALL bit in INT_MASK register will mask all interrupts.
The interrupt polarity (active high/low) can be configured with INT_MASK register's INT_ACT bit.
Once the interrupt has happened, the INT_STATUS register must be read to acknowledge the
interrupt.
See section 3.3 for INT_STATUS register details.
The SCA3060 has an internal factory trimmed oscillator and clock generator.
1. Write "10000000" (C0h) into MODE register (enable output ring buffer, BUF_EN = '1')
2. Acceleration data can be read normally
3. INT-pin is activated when buffer is ½ full, see section 2.5 for detailed INT-pin information.
1. Write "00000000" (00h) into UNLOCK register
2. Write "01010000" (50h) into UNLOCK register
3. Write "10100000" (A0h) into UNLOCK register
4. Write "00001011" (0Bh) into CTRL_SEL register (to select indirect OUT_CTRL register)
5. Write "00000101" (03h) into CTRL_DATA register (this data is written into OUT_CTRL
6. Write "10000001" (81h) into INT_MASK register (set buffer interrupt level to ¾ full,
7. Write "11000000" (C0h) into the MODE register (enable output ring buffer, BUF_EN = '1',
8. Acceleration data can be read normally for all axis and with full resolution. The buffer data
9. INT-pin is activated when the output ring buffer is ¾ full of Z-axis acceleration data, see
1. If at least one of MD bits in INT_STATUS register is "1", motion has been detected.
2. If BUF_FULL bit is "1", Ring Buffer is 75% full. Correspondingly, if BUF_HALF is "1", the
register, store Z-axis data, BUF_Z_EN = '1', divide data rate by 2, BUF_RATE = '01')
BUF_F_EN = '1', set INT-pin to active high, INT_ACT = '1')
set data length to 8 bits, BUF_8BIT = '1')
can be read from BUF_DATA register
section 2.5 for detailed INT-pin information.
Ring Buffer is 50% full.
example,
addition,
the output Ring Buffer is configured to sample only the Z-axis acceleration
the SCA3060 is configured to give an interrupt when the output ring buffer
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Unlock sequence for register lock
SCA3060 Series
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Rev B