Motorola DSP56305 User Manual page 565

movep X:M_DRXR,a0
jclr #2,X:M_DSR,*
movep X:M_DRXR,r0
move r0,r1
do a0,_LOOP5
_LBLK
jset #2,X:M_DSR,_LBLL
jclr #3,X:M_DSR,_LBLK
bra <TERMINATE
_LBLL
movep X:M_DRXR,P:(R0)+
nop
_LOOP5
bra <FINISH
;========================================================================
EPRSCILD
jclr #1,omr,EPROMLD
jclr #0,omr,SCILD
;========================================================================
; This is the routine for 56301-to-56301 boot.
; MD:MC:MB:MA=1011 - HI32 in UB mode, double strobe, HTA pin active low
UB3HOSTLD
movep #$268000,x:M_DCTR ; HM=$2 (UB)
bra <UB3_CONT
;========================================================================
; This is the routine that loads from the SCI.
; MD:MC:MB:MA=1010 - external SCI clock
SCILD
movep #$0302,X:M_SCR
movep #$C000,X:M_SCCR
movep #7,X:M_PCRE
do #6,_LOOP6
jclr #2,X:M_SSR,*
movep X:M_SRXL,A2
MOTOROLA
; Store number of words
; Wait for SRRQ to go high (i.e. data ready)
; Store starting address
; save r0
; Load instruction words
; Wait for SRRQ to go high (i.e. data ready)
; If HF0=1 stop loading data. Else check SRRQ.
; Terminate loop (enddo) and finish
; Store 24-bit data in P mem.
; movem cannot be at LA.
; and go get another 24-bit word.
; finish bootstrap
;
; If MD:MC:MB:MA=1001, go load from EPROM
; If MD:MC:MB:MA=1010, go load from SCI
; If MD:MC:MB:MA=1011, 56301-to-56301 boot
; HIRD=0 (HIRQ_ pin - open drain)
; HIRH=1 (HIRQ_ pin - handshake enabled)
; HRSP=1 (HRST pin - active low)
; HDRP=0 (HDRQ pin - active high)
; HTAP=1 (HTA pin - active low)
; HDSM=0 (Double-strobe pin mode enabled)
; continue
; Configure SCI Control Reg
; Configure SCI Clock Control Reg
; Configure SCLK, TXD and RXD
; get 3 bytes for number of
; program words and 3 bytes
; for the starting address
; Wait for RDRF to go high
; Put 8 bits in A2
DSP56305 User's Manual
Bootstrap Code
A-11