This code example shows how to use a portion of the internal flash memory of XMC™ MCUs as an emulated EEPROM memory, and provides the necessary APIs to perform read and write operations to the emulated EEPROM.

This code example does the following:

1. Initializes an EEPROM block of size 64 bytes in the internal flash of the XMC™ MCU

2. Reads and prints the existing data from the EEPROM block

3. Adds '1' to each byte read from the EEPROM block and writes the new data back to the EEPROM

4. Reads and prints the new data from the EEPROM block

View this README on GitHub.

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• ModusToolbox™ software v3.0
• SEGGER J-Link software
• Programming language: C
• Associated parts: All XMC™ MCU parts

• GNU Arm® embedded compiler v10.3.1 (GCC_ARM) - Default value of TOOLCHAIN
• Arm® compiler v6.16 (ARM)
• IAR C/C++ compiler v9.30.1 (IAR)

• XMC1100 boot kit (KIT_XMC11_BOOT_001)
• XMC1200 boot kit (KIT_XMC12_BOOT_001)
• XMC1300 boot kit (KIT_XMC13_BOOT_001)
• XMC1400 boot kit (KIT_XMC14_BOOT_001)
• XMC4200 Platform2GO XTREME kit (KIT_XMC_PLT2GO_XMC4200)
• XMC4300 relax EtherCAT kit (KIT_XMC43_RELAX_ECAT_V1)
• XMC4400 Platform2GO XTREME kit (KIT_XMC_PLT2GO_XMC4400)
• XMC4500 relax kit (KIT_XMC45_RELAX_V1)
• XMC4700 relax kit (KIT_XMC47_RELAX_V1) - Default value of TARGET
• XMC4800 relax EtherCAT kit (KIT_XMC48_RELAX_ECAT_V1)

This example uses the board's default configuration. See the kit user guide to ensure that the board is configured correctly.

For XMC4500 relax kit, an external USB-UART bridge is required to view the log messages through UART.

Install a terminal emulator if you don't have one. Instructions in this document use Tera Term.

This example requires no additional software or tools.

Create the project and open it using one of the following:

project-creator-cli --board-id KIT_XMC47_RELAX_V1 --app-id mtb-example-xmc-flash-eeprom --user-app-name FlashEEPROM --target-dir "C:/mtb_projects"

1. Connect the board to your PC using a micro-USB cable through the debug USB connector.

2. Program the board using Eclipse IDE for ModusToolbox™ software:

   1. Select the application project in the Project Explorer.

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

3. Verify that the following log messages are displayed on the UART terminal:

   Figure 1. Log messages

   

You can debug the example to step through the code. In the IDE, use the <Application Name> Debug (JLink) configuration in the Quick Panel. For more details, see the "Program and debug" section in the Eclipse IDE for ModusToolbox™ software user guide.

The main function calls only the E_EEPROM_example() function, which consists of three steps as follows:

• Step 1: Initializes the read and write data buffer in the RAM. The read data buffer is defined by the data_rbuffer[E_EEPROM_SIZE] array and the write data buffer is defined by the data_wbuffer[E_EEPROM_SIZE] array. They are used to save the data from the flash memory and to write to the flash memory.

• Step 2: Initializes the emulated EEPROM application using the E_EEPROM_XMC4_Init function for XMC4000 series devices and the E_EEPROM_XMC1_Init() function for XMC1000 series devices, and copies the latest saved data from the flash to the reserved RAM buffer.

• Step 3: Reads the data from the EEPROM block. Afterward, it increments the read data by 1 and programs it back to the EEPROM. Finally, it reads and prints the new data from the EEPROM. For XMC1000 series devices, all the sub-steps are performed inside the E_EEPROM_test() function called from the E_EEPROM_example() function. For XMC4000 series devices, all the sub-steps are programmed inside the E_EEPROM_example() function.

Note: For XMC1000 series devices: Before starting, make sure that the flash does not contain any data in the EEPROM area. Erase the EEPROM area using XMC_FLASH_ErasePages() API. In the main.c file, uncomment the function call E_EEPROM_erase(), and then build and program. Once the example runs successfully, the function call can be commented for future builds to ensure data retention. The log messages on the UART window appear as shown in Figure 2.

Figure 2. Log messages when erase operation is performed

The project uses a custom design.modus file because the following settings were modified in the default design.modus file.

Figure 3. USIC (UART) settings

Figure 4. UART Tx pin settings

Figure 5. UART Rx pin settings

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.

For XMC™ MCU devices, see 32-bit XMC™ industrial microcontroller based on Arm® Cortex®-M.

Document title: CE232589 – XMC™ MCU: Flash EEPROM

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