Intel 8XC196MH Manuale Utente

8-6

; followed by a short (1 ms) pause, thus generating a MFM waveform.
;
; This program is assembled to run on the MD demo board.
;
;**************************************
; CONSTANT AND VARIABLE DECLARATIONS
;**************************************
; Program equates
; This section defines the constants used by this program. 
; They can be changed at assembly time as required.
;**************************************
;
zero_time           equ       1000           ;1 ms
zero_pause_time     equ       zero_time
one_time            equ       2000           ;2 ms
one_pause_time      equ       one_time
carrier_freq        equ       25             ;40 KHz
buf_size            equ       8              ;size of data buffer (bytes)
fill_char           equ       10100011b      ;initial data for buffer
;
;**************************************
; SFR equates in a 32-byte window
; This section defines SFR locations as seen through a window
; to allow using compact read-modify-write instructions.
;**************************************
;
p2_mode_w      equ       0f0H           ;WSR = 7EH  1FD0H
p2_dir_w       equ       0F2H           ;WSR = 7EH  1FD2H
p2_reg_w       equ       0F4H           ;WSR = 7EH  1FD4H
p2_pin_w       equ       0F6H           ;WSR = 7EH  1FD6H
;
p7_mode_w      equ       0f1H           ;WSR = 7EH  1FD1H
p7_dir_w       equ       0F3H           ;WSR = 7EH  1FD3H
p7_reg_w       equ       0F5H           ;WSR = 7EH  1FD5H
p7_pin_w       equ       0F7H           ;WSR = 7EH  1FD7H
;
timer1_w       equ       0FAH           ;WSR = 7BH  1F7AH
comp3_con_w    equ       0E4H           ;WSR = 7BH  1F64H
comp3_time_w   equ       0E6H           ;WSR = 7BH  1F66H
;
;**************************************
; Other SFR equates
; This section defines the locations of the frequency generator SFRs.
;**************************************
;
freq_gen

equ       1FB8H

freq_cnt

equ       1FBAH

;
;**************************************
; Variable storage area
; This section defines the variables used by this program.
;**************************************
;
rseg at 30h
;
rism:          dsb  13                  ;reserved for RISM
;
rseg at 40h