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Question: I have used the UART TX8 user module to implement a serial transmitter along with CSD. When CSD is started, TX8 stops working. What is the reason for this and what is the workaround? Is there a way I can implement a full duplex UART along with CSD?Answer: The CSD user module uses all or few of the VC1, VC2 and VC3 clock dividers depending on the device used (CY8C21x34 or CY8C24x94). The value of these dividers get configured according to the Scan Speed and Resolution parameters selected in the CSD user module parameters. When you use the VC1, VC2 and VC3 dividers to generate the clock to the UART, TX8 or RX8 user module, the CSD user module API code overwrites the clock dividers when the CSD_Start function is called. Following are some of the options that may be used to implement CSD and UART in the same project.
Question: How do I improve the immunity of my Capsense board to EMI and RFI?Answer: The immunity of the Capsense board to EMI and RFI can be improved by adding a series resistor between the capsense sensor pad and the PSoC pin, thus creating a low pass filter using this series resistor and the capacitance of the PSoC pin. The capacitance of the GPIO pins of PSoC is between 3.5pF to 10pF. For optimum EMI and RFI performance, use a 560 ohm series resistance between the capsense pad and the pin. Place this resistance as close as possible to the PSoC pin. If the Capsense board seems to be susceptible to certain frequencies in the EMI / RFI spectrum, the value of this resistance can be tuned to improve the performance.
The project builds a proximity sensor using the CSD user module in the CY8C21434 device. A loop of wire is used as a sensor and when a hand approaches the sensor, a speaker is activated with a 1.4KHz signal. The raw counts, baseline and the difference counts are monitored using a CY3240 USB-I2C bridge.This project is a supplement to the video, "Create a Proximity Sensor"
This video demonstrates the method of implementing a proximity sensor using a simple loop of wire and PCB tracks. It also explains some of the key factors which determine the maximum distance which can be sensed using a piece of wire or a PCB track. CY3213-CapSense board and CY3240-I2CUSB bridge from Cypress Semiconductors have been used in the demo. Data corresponding to the capacitance of the sensor is displayed in the data logger application of CY3240 USBI2C bridge running on a laptop.The project for the video can be found below. Proximity Sensing - CSD |