PULPino is an open-source microcontroller system, based on a small 32-bit RISC-V core developed at ETH Zurich. The core has an IPC close to 1, full support for the base integer instruction set (RV32I), compressed instructions (RV32C) and partial support for the multiplication instruction set extension (RV32M). It implements several ISA extensions such as: hardware loops, post-incrementing load and store instructions, ALU and MAC operations, which increase the efficiency of the core in low-power signal processing applications.