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Сигнальный МП Motorola DSP56002.pdf
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Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

SERIAL COMMUNICATION INTERFACE (SCI)

 

+5 V

 

 

 

DSP56002

Serial

 

 

 

Bootstrap

 

DR

 

Loader

 

BR

 

(1 start,

 

HACK

RXD

8 data,

FROM OPEN

WT

1 stop,

COLLECTOR

MODA/IRQA

 

no parity,

BUFFER

 

 

LSB first)

 

MODC/NMI

TXD

 

 

MBD301*

 

 

 

MBD301*

SCLK

16xCLK

 

 

 

FROM

 

 

 

RESET

RESET

 

 

FUNCTION

 

 

 

 

MBD301*

 

 

FROM OPEN

 

 

 

COLLECTOR

MODB/IRQB

 

 

BUFFER

 

 

 

 

 

Notes: 1. *These diodes must be Schottky diodes.

 

 

 

2. All resistors are 15KΩ unless noted otherwise.

 

 

 

3. When in RESET, IRQA, IRQB and NMI must

 

 

 

be deasserted by external peripherals.

Figure 6-37 DSP56002 Bootstrap Example - Mode 6

6 - 72 PORT C MOTOROLA

For More Information On This Product, Go to: www.freescale.com

Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

SERIAL COMMUNICATION INTERFACE (SCI)

;This routine loads from the SCI.

;MC:MB:MA=110 - external SCI clock

;MC:MB:MA=111 - reserved

SCILD

MOVEP

#$0302,X:SCR

; Configure SCI Control Reg

 

JMP

<EXTC

; go to next boot rom segment

 

NOP

 

; just to fill the last space

 

ORG

PL:$100,PL:$100

; starting address of 2nd ROM

EXTC

MOVEP

#$C000,X:SCCR

; Configure SCI Clock Control Reg

 

MOVEP

#7,X:PCC

; Configure SCLK, TXD and RXD

_SCI1

DO

#6,_LOOP6

; get 3 bytes for number of

 

 

 

; program words and 3 bytes

 

 

 

; for the starting address

 

JCLR

#2,X:SSR,*

; Wait for RDRF to go high

 

MOVEP

X:SRXL,A2

; Put 8 bits in A2

 

JCLR

#1,X:SSR,*

; Wait for TDRE to go high

 

MOVEP

A2,X:STXL

; echo the received byte

 

REP

#8

 

 

ASR

A

 

_LOOP6

 

 

 

 

MOVE

A1,R0

; starting address for load

 

MOVE

A1,R1

; save starting address

 

DO

A0,_LOOP4

; Receive program words

 

DO

#3,_LOOP5

 

 

JCLR

#2,X:SSR,*

; Wait for RDRF to go high

 

MOVEP

X:SRXL,A2

; Put 8 bits in A2

 

JCLR

#1,X:SSR,*

; Wait for TDRE to go high

 

MOVEP

A2,X:STXL

; echo the received byte

 

REP

#8

 

 

ASR

A

 

_LOOP5

 

 

 

 

MOVEM

A1,P:(R0)+

; Store 24-bit result in P memory

_LOOP4

 

 

 

Figure 6-38 Bootstrap Code Fragment

MOTOROLA PORT C 6 - 73

For More Information On This Product, Go to: www.freescale.com

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