ATAVRQTOUCHX Atmel, ATAVRQTOUCHX Datasheet - Page 25

• Manufacturer Part Number: ATAVRQTOUCHX
• Description: BOARD EVAL CAPACITIVE TOUCH
• Manufacturer: Atmel
• Series: QTouch™r

Specifications of ATAVRQTOUCHX

• Sensor Type: Touch, Capacitive
• Sensing Range: 1 Slider, 1 Wheel, 2 Buttons
• Interface: USB
• Voltage - Supply: 5V, USB
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: AT90USB1287, ATxmega128A1
• Silicon Manufacturer: Atmel
• Silicon Family Name: ATxmega
• Kit Contents: Board
• Svhc: No SVHC (15-Dec-2010)
• Core Architecture: AVR
• Core Sub-architecture: AVR19
• Kit Features: One Slider, One Wheel And 2
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Sensitivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

5.6.4.2
Structure
Input / Output
Use
Fields
qt_recal_threshold
qt_di
qt_drift_hold_time
qt_max_on_duration
qt_neg_drift_rate
qt_pos_drift_rate
qt_pos_recal_delay
The measurement limit for touch sensing using QTouch acquisition method is hard coded as
8192.
The QTouch library exports a variable of this type so that the user can specify the threshold
parameters for the library. The API qt_set_parameters() should be called to apply the parameters
specified.
extern
5.6.4.3
Structure
Input / Output
Use
Fields
channel_signals
channel_references
qt_touch_status
The QTouch library exports a variable of this type which can be accessed to retrieve the touch
status of all the sensors.
extern qt_touch_lib_measure_data_t
5.6.4.4
Structure
Input / Output
Use
qt_touch_lib_config_data_t
qt_touch_lib_measure_data_t
qt_burst_lengths
qt_touch_lib_config_data_t qt_config_data;
qt_touch_lib_config_data_t
Input to the library
Global Configuration data settings for the library.
qt_touch_lib_measure_data_t
Output from the library
Data structure which holds the sensor and channel states and values.
qt_burst_lengths
Input to the library
NOTE: Applicable only to the QMatrix acquisition method libraries
Type
uint16_t
uint16_t
qt_touch_status_t
Type
recal_threshold_t
uint8_t
uint8_t
uint8_t
uint8_t
uint8_t
uint8_t
Comment
The measured signal on each channel.
The reference signal for each channel.
The state and position of the configured sensors
Comment
Sensor recalibration threshold. Default: RECAL_50 (recalibration
threshold = 50 percent of detection threshold. Refer to section
5.3.1 Recalibration Threshold
Sensor detect integration (DI) limit. Default value: 4. Refer to
section
Sensor drift hold time in units of 200 ms. Default value: 20 (20 x
200 ms = 4s), that is hold off drifting for 4 seconds after leaving
detect. Refer to section
Sensor maximum on duration in units of 200 ms. For example:
150 = recalibrate after 30s (150 x 200 ms). 0 = recalibration
disabled Default value: 0 (recalibration disabled). Refer to
section
Sensor negative drift rate in units of 200 ms. Default value: 20
(20 x 200 ms = 4s per LSB). Refer to section
Negative Drift
Sensor positive drift rate in units of 200 ms. Default value: 5 (5 x
200 ms = 1s per LSB). Refer to section
Drift
Sensor positive recalibration delay. Default: 3. Refer to section
5.3.6 for more details.
for more details
5.3.2 Detect Integration
5.3.4 Maximum ON Duration
qt_measure_data;
for more details
5.3.3 Drift Hold Time
more details
for more details
for more details.
5.3.5 Positive / Negative
for more details
5.3.5 Positive /
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