Motorola MC68340 manual DMA Module Signals

Models: MC68340

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Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

IPIPE

This active-low output signal is used to track movement of words through the instruction pipeline.

DSO

This development serial output signal helps to provide serial communications for background debug mode.

2.11.3 Breakpoint (BKPT)

This pin functions as BKPT in normal operation and as DSCLK in background debug mode.

BKPT

This active-low input signal is used to signal a hardware breakpoint to the CPU32.

DSCLK

This development serial clock input helps to provide serial communications for background debug mode.

2.11.4 Freeze (FREEZE)

Assertion of this active-high output signal indicates that the CPU32 has acknowledged a breakpoint and has initiated background mode operation.

2.12 DMA MODULE SIGNALS

The following signals are used by the direct memory access (DMA) controller module to provide external handshake for either a source or destination. See Section 6 DMA Module for additional information on these signals.

2.12.1 DMA Request (DREQ2, DREQ1)

This active-low input is asserted by a peripheral device to request an operand transfer between that peripheral and memory. The assertion of DREQstarts the DMA process. The assertion level in external burst mode is level sensitive; in external cycle steal mode, it is falling-edge sensitive.

2.12.2 DMA Acknowledge (DACK2, DACK1)

This active-low output is asserted by the DMA to signal to a peripheral that an operand is being transferred in response to a previous transfer request.

2.12.3DMA Done (DONE2, DONE1)

This active-low bidirectional signal is asserted by the DMA or a peripheral device during any DMA bus cycle to indicate that the last data transfer is being performed. DONEis an active input in any mode. As an output, it is only active in external request mode. An external pullup resistor is required even during operation in the internal request mode.

2- 10MC68340 USER’S MANUALMOTOROLA

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Motorola MC68340 manual DMA Module Signals

MC68340 specifications

The Motorola MC68340 is a highly integrated microprocessor that was introduced in the early 1990s. It belongs to the 68000 family of microprocessors and is designed to cater to the demands of embedded systems, particularly in telecommunications and networking applications. This chip represents a significant evolution in microprocessor technology by combining a microprocessor core with additional peripherals on a single chip, making it an attractive solution for engineers looking to design compact and efficient systems.

One of the key features of the MC68340 is its 32-bit architecture, which allows for significant processing power and data handling capabilities. This architecture enables the processor to handle larger data sizes and perform more complex calculations compared to its 16-bit predecessors. The MC68340 operates at clock speeds typically ranging from 16 MHz to 25 MHz. Its dual instruction pipeline enhances throughput, allowing for simultaneous instruction fetches and executions, which significantly boosts performance.

A notable characteristic of the MC68340 is the inclusion of integrated peripherals, which help reduce the overall component count in a system. Key integrated components include a memory management unit (MMU), a direct memory access (DMA) controller, and various communication interfaces such as serial ports. The memory management capabilities enhance the processor's ability to manage memory resources efficiently, enabling it to support multitasking environments commonly found in modern computing.

In terms of connectivity, the MC68340 features connections for both synchronous and asynchronous serial communication, making it well-suited for networking tasks. The processor supports a range of bus standards, including address and data buses, which facilitate seamless interaction with peripheral devices.

Another important aspect of the MC68340 is its flexibility. The processor supports multiple operating modes, including multiple CPU configurations and compatibility with the Motorola 68000 family, allowing for easier integration into existing systems.

Moreover, the MC68340 boasts low power consumption compared to many of its contemporaries, making it an excellent choice for battery-operated applications, enhancing its appeal in sectors like telecommunications, industrial control, and automotive systems. Its combination of performance, integration, versatility, and efficiency has secured the MC68340 a reputable position in the annals of embedded systems technology, proving to be a valuable asset for developers and engineers alike.