Bought from here.

user manual：           https://github.com/wuxx/icesugar-nano/blob/main/README.md
win 7 serial driver：   https://github.com/wuxx/icesugar-nano/blob/main/doc/usbser.inf
source and semantics：     https://github.com/wuxx/icesugar-nano

Follow https://projectf.io/posts/building-ice40-fpga-toolchain/ . If you got this error: fatal error: ‘ftdi.h’ file not found, then modify config.mk in /Users/peter/workspace/icestorm:

Edit /Users/peter/workspace/icestorm/iceprog/Makefile

All examples in https://github.com/wuxx/icesugar-nano , just drag the demo program from demo folder or build it from src folder.