觸控設(shè)備手勢(shì)喚醒的設(shè)計(jì)思路及其實(shí)現(xiàn)
// this handles hardware-level interrupts on the micro
__interrupt void irq_handler( void )
{
...
// if the hardware interrupt came from the MAX44000 sensor
// pulling its INT pin low
if ( irq_source == MAX44000 )
{
// if the device is in sleep mode
if (device_status == SLEEP_MODE)
{
device_status = WAKE_MODE; // wake up the device
...
// reconfigure whatever else you need here as the system wakes up
}
// otherwise, handle it however it is you wish
else
{
...
}
}
...
}
/**
* configure_max44000_for_sleep_mode()
*
* Sets up the MAX44000 to trigger a hardware interrupt when the proximity
* counts go above some set threshold.
*
* Arguments:
* uint8 upper_threshold - the set threshold (8-bit mode)
*
* Returns:
* n/a
*/
void configure_max44000_for_sleep_mode(uint8 upper_threshold)
{
uint8 max44000_thresh_registers[] = {0x0B,0x0C};
uint8 max44000_upper_thresh[] = {0x40,0};
max44000_upper_thresh[1] = upper_threshold;
// do a consecutive write of 0 followed by upper_threshold to
// registers 0xB and 0xC, respectively
// MAX44000_ADDR is usually 0x94
// interrupt will trigger only if proximity value is above the threshold
write_i2c_register(MAX44000_ADDR,max44000_thresh_registers,
max44000_upper_thresh,2);
// write to bits 2 and 3 of register 0x0A here if you wish to set the
// persist time to anything other than one sample
// writes to register 0x01 to enable interrupts on the MAX44000
max44000_enable_interrupt();
return;
}
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