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Motorola DSP56301 user manual Synchronous Mode, Asynchronous Mode, Multidrop Mode

Models: DSP56301

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Operating Modes

transmit and receive clock compatible with the Intel 8051 serial interface mode 0 synchronizes data. Asynchronous modes are compatible with most UART-type serial devices. Standard RS-232 communication links are supported by these modes. Multidrop Asynchronous mode is compatible with the MC68681 DUART, the M68HC11 SCI interface, and the Intel 8051 serial interface.

8.1.1Synchronous Mode

Synchronous mode (SCR[WD2–0]=000, Shift Register mode) handles serial-to-parallel and parallel-to-serial conversions. In Synchronous mode, the clock is always common to the transmit and receive shift registers. As a controller (synchronous master), the DSP puts out a clock on the SCLK pin. To select master mode, choose the internal transmit and receive clocks (set TCM and RCM=0).

As a peripheral (synchronous slave), the DSP accepts an input clock from the SCLK pin. To select the slave mode, choose the external transmit and receive clocks (TCM and RCM=1). Since there is no frame signal, if a clock is missed because of noise or any other reason, the receiver loses synchronization with the data without any error signal being generated. You can detect an error of this type with an error detecting protocol or with external circuitry such as a watchdog timer. The simplest way to recover synchronization is to reset the SCI.

8.1.2Asynchronous Mode

Asynchronous data uses a data format with embedded word sync, which allows an unsynchronized data clock to be synchronized with the word if the clock rate and number of bits per word is known. Thus, the clock can be generated by the receiver rather than requiring a separate clock signal. The transmitter and receiver both use an internal clock that is 16 times the data rate to allow the SCI to synchronize the data. The data format requires that each data byte have an additional start bit and stop bit. Also, two of the word formats have a parity bit. The Multidrop mode used when SCIs are on a common bus has an additional data type bit. The SCI can operate in full-duplex or half-duplex modes since the transmitter and receiver are independent.

8.1.3Multidrop Mode

Multidrop is a special case of asynchronous data transfer. The key difference is that a protocol allows networking transmitters and receivers on a single data-transmission line. Inter-processor messages in a multidrop network typically begin with a destination address. All receivers check for an address match at the start of each message. Receivers with no address match can ignore the remainder of the message and use a wakeup mode to enable the receiver at the start of the next message. Receivers with an address match can receive the

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DSP56301 User’s Manual

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Motorola DSP56301 user manual Synchronous Mode, Asynchronous Mode, Multidrop Mode
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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.