ESSI Programming Model

7.5.5ESSI Receive Data Register (RX)

The Receive Data Register (RX) is a 24-bit read-only register that accepts data from the receive shift register as it becomes full, according to Figure 7-12and Figure 7-13. The data read is aligned according to the value of the ALC bit. When the ALC bit is cleared, the MSB is bit 23, and the least significant byte is unused. When the ALC bit is set, the MSB is bit 15, and the most significant byte is unused. Unused bits are read as 0. If the associated interrupt is enabled, the DSP is interrupted whenever the RX register becomes full.

7.5.6ESSI Transmit Shift Registers

The three 24-bit transmit shift registers contain the data being transmitted, as in Figure 7-12and Figure 7-13. Data is shifted out to the serial transmit data signals by the selected (whether internal or external) bit clock when the associated frame sync I/O is asserted. The word-length control bits in CRA determine the number of bits that must be shifted out before the shift registers are considered empty and can be written again. Depending on the setting of the CRA, the number of bits to be shifted out can be 8, 12, 16, 24, or 32. Transmitted data is aligned according to the value of the ALC bit. When ALC is cleared, the MSB is Bit 23 and the least significant byte is unused. When ALC is set, the MSB is Bit 15 and the most significant byte is unused. Unused bits are read as 0. Data shifts out of these registers MSB first if the SHFD bit is cleared and LSB first if SHFD is set.

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DSP56301 User’s Manual

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Motorola DSP56301 user manual Essi Receive Data Register RX, Essi Transmit Shift Registers

DSP56301 specifications

The Motorola DSP56301 is a highly efficient digital signal processor, specifically engineered for real-time audio and speech processing applications. This DSP is part of Motorola's renowned DSP56300 family, which is recognized for its innovative features and outstanding performance in the realm of digital signal processing.

One of the main features of the DSP56301 is its ability to handle complex computations at high speeds. With a maximum clock frequency of 66 MHz, it delivers fast performance, enabling it to process audio signals in real time. The chip is built on a 24-bit architecture, which allows for high-resolution audio processing. This is particularly beneficial in applications such as telecommunications, consumer audio devices, and professional audio equipment, where precision is paramount.

The DSP56301 boasts a comprehensive instruction set that includes efficient mathematical operations, which are essential for digital filters and audio effects processing. One of the key innovations of this device is its dual data path architecture, which permits simultaneous processing of multiple data streams. This feature significantly enhances the device's throughput and responsiveness, making it suitable for demanding applications such as voice recognition and synthesis.

In terms of memory regions, the DSP56301 includes several on-chip memory categories, such as program memory, data memory, and a specialized memory for coefficients. The architecture's support for external memory expansion further increases its versatility, allowing designers to tailor systems to their specific requirements.

The DSP56301 implements advanced features such as a powerful on-chip hardware multiplier and accumulator, simplifying complex mathematical tasks and accelerating the execution of algorithms. Its flexible interrupt system enhances its capability to respond to time-sensitive operations, while the integrated serial ports facilitate efficient data communication with external devices.

Power consumption is also a vital characteristic of the DSP56301. It is designed with energy efficiency in mind, allowing for extended operation in battery-powered devices. The chip’s low power requirements are particularly advantageous in portable audio devices and other applications where energy conservation is crucial.

In conclusion, the Motorola DSP56301 is an exceptional digital signal processor that combines high processing power, flexibility, and efficiency. Its main features, advanced technologies, and robust architecture make it a top choice for developers seeking to create sophisticated audio and signal processing systems. With its enduring legacy in the industry, the DSP56301 continues to be relevant in a variety of modern applications, ensuring it remains a valuable tool for engineers and designers.