ST ST7 - Page 174

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6 - STMicroelectronics Programming Tools
The main program is the following:
ST7/
;=============================================================
;= Main (caterpillar) =
;=============================================================
#include "Register.inc"
EXTERN Delay500 ; By default, external label defined as a word
; definition of the constants
; =========================
BYTES ; The following constants defined as bytes
watch EQU $FF
cpudiv2 EQU 0 ; normal speed
segment 'rom'
WORDS ; Next labels are words.
; Initialisations
; ===============
reset:
ld a, #cpudiv2
ld miscr, a ; fq 8MHz /2 = CPU clock = 4MHz
ld a, #watch
ld wdgr, a ; Start watchdog
ld paddr, a ; port A as output
clr paor ; open drain, no pull up
ld padr, a ; leds off
rsp ; initialize stack
; Main program
; ============
Start:
ld x, #00
Next:
ld a, (table,x)
ld padr, a ; Switch one LED on pa0 OFF, others ON
call Delay500 ; according to table contents
inc x
cp x, #08 ; If at end of table, go back to the beginning
jreq Start
jra Next
; table of the patterns that are output in sequence
; =================================================
table: dc.b 1, 2, 4, 8, 16, 32, 64, 128
; Interrupt vectors
; =======================
segment 'vectit' ; ($FFE0)
DC.W 0 ; skip 8 vectors
DC.W 0
DC.W 0
DC.W 0
DC.W 0