A.3 Bootstrap Program Listing - Motorola DSP56009 User Manual

Bootstrap ROM Contents
A.3 BOOTSTRAP PROGRAM LISTING
; BOOTSTRAP CODE FOR DSP56009—(C) Copyright 1995 Motorola Inc.
; Revised April 16, 1995.
;
; Bootstrap through EMI, SHI-SPI and SHI-I2C, according to op-modes MC:MB:MA.
;
; Occupies 32 words of bootstrap ROM in the address range P:$0-P:$1F
bcr equ
gpior equ
gdd3 equ
gd3 equ
ecsr equ
edrr0 equ
ebar0 equ
eor0 equ
edrf equ
hrne equ
hrx equ
hcsr equ
hi2c equ
ma equ
mb equ
mc equ
org
start clr a
bset
jclr
clr a
movep
jset
; This is the routine that loads from external EPROM.
A-4
$fffe ; BCR Register
$fff7 ; GPIO Control/Data Register
11 ; direction bit for GPIO3
3 ; data bit for GPIO3
$ffeb ; EMI Control/Status Register
$ffea ; EMI Data Read Register
$ffe8 ; EMI Base Address Register 0
$ffe9 ; EMI Offset Register
13 ; EMI EDRR Full flag
17 ; SHI FIFO Not Empty flag
$fff3 ; SHI HRX FIFO
$fff1 ; SHI Control/Status Register
1 ; SHI IIC Enable Control Bit
0 ; OMR Mode A
1 ; OMR Mode B
4 ; OMR Mode C
p:$0 ; bootstrap code starts at $0
#<0,r0 ; r0 points to internal Program RAM
#13,a0 ; Program ROM starting address ($2000)
#ma,omr,exit ; if MC:MB:MA = xx0 goto Program ROM
; downld
#$A9,r1 ; clear a0—Program ROM starting
; address,prepare SHI control
; value in r1
; HEN = 1, HI2C = 0, HM1-HM0 = 10,
; HFIFO = 1, HMST = 0,
; HRQE1-HRQE0 = 01, HIDLE = 0,
; HBIE = 0, HTIE = 0,
; HRIE1-HRIE0 = 00
a1,x:ebar0 ; EPROM starting address
#mc,omr,shild ; If MC:MB:MA = 1x1 load from
; SHI
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