47 lines
1.6 KiB
Plaintext
47 lines
1.6 KiB
Plaintext
Overview
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========
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This example shows how to use CAPT to detect key touch event.
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When the key is touched, LED on the board is on accordingly.
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The example first runs the calibration, in this period, all LEDs
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are on, please don't touch any key at this time. After all LEDs off
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the example starts touch detection, touch any key and the LED turns on.
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This example only supports touch one key at the same time.
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CAPT sample data are saved in a window for later process.
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During calibration period, the variance of each channel is used to judge
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whether the channel is stable. Calibration finished only when all channels
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are stable. The stable value after calibration is saved as baseline, to
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be used in the detection stage.
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To remove touch glitch, a software filter is used in this example.
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Toolchain supported
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===================
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- IAR embedded Workbench 9.10.2
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- Keil MDK 5.34
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- GCC ARM Embedded 10.2.1
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- MCUXpresso 11.5.0
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Hardware requirements
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=====================
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- Micro USB cable
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- LPC845 Breakout board
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- Personal Computer
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Board settings
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==============
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Make sure R23 is on the LPC845 Breakout board.
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Prepare the demo
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1. Connect a micro USB cable between the PC host and the CMSIS DAP USB port on the board.
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2. Open a serial terminal with the following settings:
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- 9600 baud rate
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- 8 data bits
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- No parity
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- One stop bit
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- No flow control
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3. Download the program to the target board.
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4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.
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Running the demo
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================
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When touch the electrode plate, the corresponding LED would turn on.
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