Silicon Labs offers full featured development kits that are both economical and come with everything needed to evaluate hardware and develop code including: SiM3U1xx/SiM3C1xx MCU card; USB debug adaptor/programmer; power supply, cables, quick start guide; and software links to free downloadable tools, MCU code and documentation. The USB debug adaptor/programmer works with Keil, IAR, and Precision32 GNU based tools so developers can use whatever toolset they are most familiar with. Silicon Labs also offers enhanced development kits which add a motherboard, plug-in I/O expander cards and a slot for an RF card. These kits come with additional demos and software example code to enhance the development experience. The SiMC1xx-B-EDK comes with an I/O expander card with breadboard area for prototyping, LEDs to tests out high drive I/O, segment display, and more. The SiMU1xx-B-EDK comes with the I/O expander card and an audio card that adds an SD memory slot, head phones, LCD display for USB audio demos.