AS31 is a free 8051 assembler originally written by Ken Stauffer.  Versions
of AS31 found here include important bug fixes and added features, such as
standard intel-hex output format for use with PAULMON2 and EPROM programmers.
AS31 is a good tool for building small 8051-based projects that are written
in 100% 8051 assembly language.

WWW: https://www.pjrc.com/tech/8051/
