Abstract
The study in this paper has a purpose to improve our previous underwater communication acoustic modem which based on Cortex-M3. This enhanced acoustic modem has compatibility with Cortex-M3 and maintains same size. In addition, the modem has TMS320C6416 (DSP) to process complex algorithms, which Cortex-M3 (ARM) is not able to control, such as channel coding. Communication between DSP and ARM is SPI protocol and peripheral devices of DSP are RAM, ROM, DAC and ADC. Therefore, DSP can properly operate without ARM.