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Motorola DSP56301 User Manual

Page 306

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DSP56301 User’s Manual

movep X:M_DRXR,y0 ; Store starting address

insert x1,x0,a ; concatenate next 16-bit word

insert y1,y0,a ; concatenate next 16-bit word

move a1,r0 ; start to p-mem

move a0,a1 ; number of words to transfer

; Download P memory through UB

lsr a r0,r1 ; divide loop count by 2 and save r0

do a1,_LOOP4 ; Load instruction words

_LBLE

jset #2,X:M_DSR,_LBLF ; Wait for SRRQ to go high (i.e. data ready)

jclr #3,X:M_DSR,_LBLE ; If HF0=1, stop loading new data.

bra

_LBLF

movep X:M_DRXR,a0 ; Store 16-bit data in accumulator

_LBLG

jset #2,X:M_DSR,_LBLH ; Wait for SRRQ to go high (i.e. data ready)

jclr #3,X:M_DSR,_LBLG ; If HF0=1, stop loading new data.

bra

_LBLH

movep X:M_DRXR,x0 ; Store 16-bit data in register

_LBLI

jset #2,X:M_DSR,_LBLJ ; Wait for SRRQ to go high (i.e. data ready)

jclr #3,X:M_DSR,_LBLI ; If HF0=1, stop loading new data.

bra

_LBLJ

movep X:M_DRXR,y0 ; Store 16-bit data in register

insert x1,x0,a ; concatenate next 16-bit word

insert y1,y0,a ; concatenate next 16-bit word

movem a0,p:(r0)+ ; Store 24-bit data in P mem.

movem a1,p:(r0)+ ; Store 24-bit data in P mem.

nop ; movem cannot be at LA.

_LOOP4 ; and go get another 24-bit word.

bra

;========================================================================

; This is the routine that loads from the Host Interface in PCI mode.

; MD:MC:MB:MA=x100 - Host PCI

PCIHOSTLD

bset #20,X:M_DCTR ; Configure HI32 as PCI

UB3_CONT

jclr #2,X:M_DSR,* ; Wait for SRRQ to go high (i.e. data ready)

movep X:M_DRXR,a0 ; Store number of words

jclr #2,X:M_DSR,* ; Wait for SRRQ to go high (i.e. data ready)

movep X:M_DRXR,r0 ; Store starting address

move r0,r1 ; save r0

do a0,_LOOP5 ; Load instruction words

_LBLK

jset #2,X:M_DSR,_LBLL ; Wait for SRRQ to go high (i.e. data ready)

jclr #3,X:M_DSR,_LBLK ; If HF0=1, stop loading data. Else check SRRQ.

bra

_LBLL

movep X:M_DRXR,P:(R0)+ ; Store 24-bit data in P mem.

nop ; movem cannot be at LA.

_LOOP5 ; and go get another 24-bit word.

; finish bootstrap