Motorola MC68340 ユーザーズマニュアル

6- 40

MOTOROLA

* No interrupts are enabled, source (read) cycle. Increment source
* address, source size is long word, REQ is external burst request.
* Single-address mode, start the DMA transfers.

MOVE.W

#$1823,DMACCR1(A0)

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

END

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

Example 2: Internal Request Generation, Memory to Memory Transfers.
***************************************************************************
* MC68340 basic DMA channel register initialization example code.
* This code is used to initialize the 68340's internal DMA channel
* registers, providing basic functions for operation.
* The code sets up channel 1 for internal request generation
* memory to memory transfers.
***************************************************************************
***************************************************************************
* SIM40 equates
***************************************************************************
MBAR

EQU $0003FF00 Address of SIM40 Module Base Address Reg.

MODBASE

EQU $FFFFF000 SIM40 MBAR address value

***************************************************************************
* DMA Channel 1 equates
DMACH1

EQU $780

Offset from MBAR for channel 1 regs

DMAMCR1

EQU $0

MCR for channel 1

* Channel 1 register offsets from channel 1 base address
DMAINT1

EQU $4

interrupt register channel 1

DMACCR1

EQU $8

control register channel 1

DMACSR1

EQU $A

status register channel 1

DMAFCR1

EQU $B

function code register channel 1

DMASAR1

EQU $C

source address register channel 1

DMADAR1

EQU $10

destination address register channel 1

DMABTC1

EQU $14

byte transfer count register channel 1

SARADD

EQU $6000

source address

DARADD

EQU $8000

destination address

NUMBYTE

EQU $E

number of bytes to transfer

***************************************************************************
***************************************************************************
* Initialize DMA Channel 1
***************************************************************************

LEA

MODBASE+DMACH1,A0 Pointer to channel 1

* Initialize DMA channel 1 MCR

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Freescale Semiconductor, Inc.

For More Information On This Product,

   Go to: www.freescale.com

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