The hcs2d daemon is another member of the rcDaemon family, which in this case provides an interface to the Circuit Cellar Inc. (tm) HCS2D Supervisory Controller.
The HCS2D is controlled via a serial port. It has an 8-channel, 8-bit A to D converter and 24 bits of TTL I/O. It also has an RS-485 port thru which many additional io modules may be attached. It can be programmed to return status on its input/outputs on a periodic basis.
The HCS2D is programmed in a language called "EXPRESS". The hcs2d daemon can download such programs to the hardware, and register requests with it for status information as desired. The hcs2d daemon is compatible with the other rcDaemons.
It is possible to use the Circuit Cellar Inc. HCS2D DOS compiler under FreeBSD andPCEMU to compile HCS2D programs with this set of tools