PIC12F675 Assembly, with TM1638 display. 

Demonstrating a small, cheap, PIC dev board, with a simple display. Programmed in assembler, using the pic-as assembler provided as part of the XC8 compiler with the MPLABX IDE (all software tools are free downloads).
Source code for my demo here: ceptimus.co.uk...
Julian Ilett's tutorial on the dev board: • PIC Assembly Language ... (He used the older MPLAB software to program it, but his tutorial playlist is still relevant - the microcontroller itself hasn't changed, and still runs the same programs! You just have to format your source code slightly differently to suit the modern pic-as)