Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

***************************************************************************

*Initialization code

***************************************************************************

*Start Chip Select Initialization:

INIT340

MOVE.W #$2700,SR

Init SR - interrupts masked

***************************************************************************

* Set up default module base address value

 

MOVEQ.L

#7,D0

MBAR is in CPU space

MOVEC.L

D0,DFC

load DFC to indicate CPU space

MOVE.L

#MODBASE+1,D0

Set address/valid bit

MOVES.L

D0,MBAR

write to MBAR

***************************************************************************

*Set up system protection register:

*Software watchdog disabled, double bus fault monitor disabled, bus

*monitor BERR after 16 clocks.

MOVE.B #6,SYPCR+MODBASE

***************************************************************************

* Clock synthesizer control register:

 

* Switch from 8.3 to 16.7 MHZ

 

MOVE.W #$7F00,SYNCR+MODBASE

X-bit doubles the default speed

***************************************************************************

*Module configuration register:

*When FREEZE is asserted, software watchdog and periodic interrupt timer

*are disabled, bus monitor is enabled. Port B = 4 IRQs, 4 chip selects.

*Show Cycles enabled, external arbitration enabled. Supervisor/user

*SIM registers unrestricted, Interrupt Arbitration at priority $F

MOVE.W #$420F,MCR+MODBASE

***************************************************************************

* Now, set up Address masks and base addresses for the chip selects:

LEA

CSAM0+MODBASE,A0

Point to CS0 addr. mask location.

MOVEQ

#7,D

Set up a loop counter.

LEA

CSAM0$,A1

Point to addr mask memory location.

LOOP MOVE.L

(A1)+,(A0)+

Init. addr mask and base addr reg

DBRA

D0,LOOP

 

MOTOROLAMC68340 USER’S MANUAL4- 39

For More Information On This Product,

Go to: www.freescale.com

Page 135 Page 137
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Image 136
Motorola MC68340 Moveq.L, MOVEC.L D0,DFC, MOVE.L #MODBASE+1,D0, MOVES.L D0,MBAR, MOVE.B #6,SYPCR+MODBASE, LEA CSAM0$,A1
Page 135 Page 137

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.
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