Motorola DSP96002 User Manual page 161

; The second routine loads the internal PRAM using the Host
; Interface logic.
; If HF1=0, it will load 4,096 bytes from the external host processor.
; These will be condensed into 1,024 32-bit words and stored in
; contiguous internal PRAM memory locations starting at P:$0.
; the routine loads data starting with the least significant byte of
; P:$0 first.
; If HF1=1, it will load 1,024 32-bit words from the external host
; processor.
; If the host processor only wants to load a portion of the P memory,
; and start execution of the loaded program, the Host Interface
; bootstrap load program routine may be killed by setting HF0 = 0.
;
INLOOP DO
; This is the context switch
JSET
; This is the first routine. It loads from external P: memory.
DO
LSR
MOVEM
LSL
OR
_LOOP2 JMP
;
; This is the second routine. It loads thru the Host Interface.
_HOSTLD JSET
; Boot thru Host Interface in Port A
_HOSTA BCLR
MOVE
MOVE
JMP
; Boot thru Host Interface in Port B
_HOSTB BCLR
MOVE
MOVE
Figure 9-3. Assembler Source for DSP96002 Bootstrap Program (2 of 3)
MOTOROLA
#1024,_LOOP1 ; Load 1,024 instruction words
#1,OMR,_HOSTLD ; Perform load from Host
; Interface if MB=1.
#4,_LOOP2 ; Get 4 bytes into D0.L
#8,D0 ; Shift previous byte down
P:(R1)+,D1.L ; Get byte from ext. P mem.
#24,D1 ; Shift into upper byte
D1,D0 ; concatenate
<_STORE ; Then put the word in P memory
#0,OMR,_HOSTB ; Port A or Port B?
#5,X:M_HCRA ; Enable Port A Host Interface
#M_HSRA,R2 ; R2 points to HSRA
#M_HRXA,R3 ; R3 points to HRXA
<_HOSTR ; go to host routine
#5,X:M_HCRB ; Enable Port B Host Interface
#M_HSRB,R2 ; R2 points to HSRB
#M_HRXB,R3 ; R3 points to HRXB
DSP96002 USER'S MANUAL
Note that
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