Blockdiagram programming system for 32 bit floating point signal processor

A simple programming system has been developed for a 32 bit floating point signal processor µPD77230 [1]. The system is based on the blockdiagram language concept [2][3], in which many signal processing systems can be realized by combinations of primitive functional blocks. A wide dynamic range and high precision processing obtained from a 32 bit floating point arithmetic make this approach possible, without complex scaling or limit cycle oscillation problems encountered in a fixed point processing. About 100 primitive programs are implemented on a mask ROM sample chip. They can be used as library programs accessed by a main program stored in an external instruction memory. In addition, library programs can also be carried out by a command sequence stored in an internal memory under a special control program in the chip. This approach enables using µPD77230 processing capability without knowledge concerning its architecture or a set of microinstructions. In this paper, a DTMF receiver and an ADPCM coder, realized by this system, are shown as examples.