# Progression

The sample code offers many single-topic samples to enable you to learn about and develop one function or feature at a time in isolation. Once you are comfortable, you can work your way up to full-featured integrated samples, applying techniques you have learned from using the single function samples.

The progression from the simplest sample application to the most integrated application is:

1. Blinky: following the RSL15 Getting Started Guide to install the tools and execute blinky.
2. Single function samples: build and execute samples such as sleep, uart or SPI and experiment with configurations for your end application.
3. Wireless samples: build and execute samples such as ble_peripheral_server to experiment with a wireless Bluetooth Low Energy connection and develop configurations for your application.
4. Integrated samples: build and execute samples such as ble_peripheral_server_sleep and ble_peripheral_server_sleep_fota to learn interactions of a complete system.
5. See How to Build Your Own RSL15 Application to add additional software components such as UART to the integrated sample to form the basis of your own application.

The illustrates the progression in getting comfortable with building your own applications for RSL15.

Figure: The Firmware Developer’s Experience