Bootstrap Code
A
-6
DSP56303 User’s Manual
; HRP
= 0 Negative host request
; HCSP
= 0 Negative chip select input
; HD/HS
= 0 Single strobe bus (R/W~ and DS strobes)
; HMUX
= 0 Non multiplexed bus
; HASP
= 0 (address strobe polarity has no meaning in
;
non-multiplexed bus)
; HDSP
= 0 Negative data strobes polarity
; HROD
= 0 Host request is active when enabled
; spare = 0 This bit should be set to 0 for future
;
compatibility
; HEN
= 0 When the HPCR register is modified HEN should be
;
cleared
; HAEN
= 1 Host acknowledge is enabled
; HREN
= 1 Host requests are enabled
; HCSEN = 1 Host chip select input enabled
; HA9EN
= 0 (address 9 enable bit has no meaning in
;
non-multiplexed bus)
; HA8EN
= 0 (address 8 enable bit has no meaning in
;
non-multiplexed bus)
; HGEN
= 0 Host GPIO pins are disabled
HI08CONT
bset
#HEN,x:M_HPCR
; Enable the HI08 to operate as host
; interface (set HEN=1)
jclr
#HRDF,x:M_HSR,*
; wait for the program length to be
; written
movep
x:M_HRX,a0
jclr
#HRDF,x:M_HSR,*
; wait for the program starting address
; to be written
movep
x:M_HRX,r0
move
r0,r1
do
a0,HI08LOOP
; set a loop with the downloaded length
;
counts
HI08LL
jset
#HRDF,x:M_HSR,HI08NW
; If new word was loaded then
jump
;to read that word
jclr
#HF0,x:M_HSR,HI08LL
; If HF0=0 then continue with
the
; downloading
enddo
; Must terminate the do loop
bra
<HI08LOOP
HI08NW
movep
x:M_HRX,p:(r0)+
; Move the new word into its destination
; location in the program RAM
HI08LOOP
bra
<FINISH
;========================================================================
EPRSCILD
jclr #1,omr,EPROMLD ; If MC:MB:MA=001, go load from EPROM
;========================================================================
; This is the routine that loads from the SCI.
; MC:MB:MA=010 - external SCI clock
SCILD
movep #$0302,X:M_SCR ; Configure SCI Control Reg
Summary of Contents for DSP56303
Page 1: ...DSP56303 User s Manual 24 Bit Digital Signal Processor DSP56303UM AD Revision 1 January 2001 ...
Page 52: ...JTAG OnCE Interface 2 22 DSP56303 User s Manual ...
Page 114: ...General Purpose Input Output GPIO 5 10 DSP56303 User s Manual ...
Page 212: ...GPIO Signals and Registers 8 26 DSP56303 User s Manual ...
Page 268: ...Interrupt Equates A 22 DSP56303 User s Manual ...
Page 306: ...Programming Sheets B 38 DSP56303 User s Manual ...
Page 320: ...Index 14 DSP56303 User s Manual ...