A system and method for configuring a target hardware device. The system receives user input selecting instances of circuit-like primitives and instances of dataflow primitives. The user may wire the instances together using wires of various kinds to specify a graphical program. The wires are distinguished into types depending on whether or not they impose dataflow ordering dependencies and depending on the kind of data they are intended to carry. The circuit-like primitives may receive and/or generate digital signals to control the timing of processes or events such as A/D conversion, D/A conversion, digital input, digital output, pulse generation, etc. The circuit-like primitives and the dataflow primitives may communicate with each other through cast primitives and satellite nodes. Program code corresponding to the graphical program may be compiled to a format suitable for configuring a programmable hardware element or some other target device.