This example demonstrates multiple methods of configuring, reading, writing, and generating interrupts with PSoC™ 4 general purpose input/output (GPIO) pins. See AN86439 - PSoC™ 4 - using GPIO pins for an overview of GPIO basics, configuration options, mixed-signal use, interrupts, and low-power behavior.

View this README on GitHub.

Provide feedback on this code example.

• ModusToolbox™ v3.1 or later (tested with v3.1)
• Board support package (BSP) minimum required version: 3.1.0
• Programming language: C
• Associated parts: PSoC™ 4000S, PSoC™ 4100S, PSoC™ 4100S Plus, PSoC™ 4500S, PSoC™ 4100S Max, and PSoC™ 4000T

• GNU Arm® Embedded Compiler v11.3.1 (GCC_ARM) – Default value of TOOLCHAIN
• Arm® Compiler v6.16 (ARM)
• IAR C/C++ Compiler v9.30.1 (IAR)

• PSoC™ 4100S Max Pioneer Kit (CY8CKIT-041S-MAX) - Default value of TARGET
• PSoC™ 4100S Plus Prototyping Kit (CY8CKIT-149)
• PSoC™ 4000S CAPSENSE™ Prototyping Kit (CY8CKIT-145-40XX)
• PSoC™ 4100S CAPSENSE™ Pioneer Kit (CY8CKIT-041-41XX)
• PSoC™ 4500S Pioneer Kit (CY8CKIT-045S)
• PSoC™ 4000T CAPSENSE™ Prototyping Kit (CY8CPROTO-040T)

This example uses the board's default configuration for all the kits listed above, except few kits. Make the hardware changes as mentioned below:

• To use Port 4 header pins on CY8CKIT-045S, populate R53 to R55 and R57 to R61 with 0-Ohm resistors.
• To use the User Button on CY8CPROTO-040T, short J6.2 and J6.3 with the jumper shunt on the kit.

See the kit guide to ensure that the board is configured correctly.

Note: Some of the PSoC™ 4 kits ship with KitProg2 installed. ModusToolbox™ requires KitProg3. Before using this code example, make sure that the board is upgraded to KitProg3. The tool and instructions are available in the Firmware Loader GitHub repository. If you do not upgrade, you will see an error like "unable to find CMSIS-DAP device" or "KitProg firmware is out of date".

Use jumper wire to externally connect the reference pin (P2[0]) to either logic HIGH (3V3) or logic LOW (GND).

See the ModusToolbox™ tools package installation guide for information about installing and configuring the tools package. This example requires no additional software or tools.

The ModusToolbox™ tools package provides the Project Creator as both a GUI tool and a command line tool.

project-creator-cli --board-id CY8CKIT-041S-MAX --app-id mtb-example-psoc4-gpio --user-app-name MyGPIO --target-dir "C:/mtb_projects"

After the project has been created, you can open it in your preferred development environment.

1. Connect the Reference pin (P2.0) to logic LOW externally using a jumper wire.

2. Connect the board to your PC using the provided USB cable through the KitProg3 USB connector.

3. Program the board using one of the following:

   Using Eclipse IDE

   1. Select the application project in the Project Explorer.

   2. In the Quick Panel, scroll down, and click <Application Name> Program (KitProg3_MiniProg4).

   In other IDEs

   Follow the instructions in your preferred IDE.

   Using CLI

   From the terminal, execute the make program command to build and program the application using the default toolchain to the default target. The default toolchain is specified in the application's Makefile but you can override this value manually:

   make program TOOLCHAIN=<toolchain>
   

   Example:

   make program TOOLCHAIN=GCC_ARM
   

4. After programming, the application starts automatically.

5. Confirm that the user LED toggles twice.

6. Connect the reference pin (P2.0) to logic HIGH externally using a jumper wire. Press the user button to observe the change in the state of the user LED. When the user button is pressed, the state of the reference pin is read and written to the user LED using the Cy_GPIO_Write() PDL API.

7. Now connect the reference pin (P2.0) to logic LOW. Press the user button to observe the change in the state of the user LED.

The value on port 4 pins are incremented continuously and the toggling port pins can be monitored on an oscilloscope.

You can debug the example to step through the code.

This example demonstrates the GPIO pin configuration, reading, writing, full port access, and interrupts using multiple GPIO PDL driver methods. Use the GPIO PDL driver method suitable for your application. See the comments in the main.c file or AN86439 - PSoC™ 4 - using GPIO pins for more details on each PDL driver method.

To demonstrate individual GPIO pin access, this example reads the value from the reference pin and writes it to the user LED. The user LED toggles twice to demonstrate the set/clear function.

The user button is configured to generate an interrupt on a rising edge, which occurs on a button release. The interrupt routine reads the value from the reference pin and writes to the user LED.

A full port of GPIO pins is configured as output pins on port 4. The value on port 4 is continuously read with direct register reads, is incremented, and written back to the port. The toggling port pins can be monitored on an oscilloscope.

Table 1. Application resources

Infineon provides a wealth of data at www.infineon.com to help you select the right device, and quickly and effectively integrate it into your design.

Document title: CE231471 - PSoC™ 4: GPIO pins

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