各位大侠,我用三个7219驱动数码管,为什么只有第一个7219有反映呀?? 下面是程序,麻烦高手指点一下!!(用的是AVR单片机) scan_display: ldiw yl ,yh,display_led_buff ; 送显示地址 ldi dh ,0x01 ; 数码管1的高字节 ldi dl ,0x08 ; 8个数码管 scan_display_1: mov ah ,dh ; 高字节 ld al ,Y+ ; 低字节 rcall write_word_to_7219_A ; 写入A inc dh dec dl cpi dl ,0 brne scan_display_1 ldiw yl ,yh,display_led_buff+8 ldi dh ,0x01 ldi dl ,0x08 scan_display_2: mov ah ,dh ld al ,Y+ rcall write_word_to_7219_B inc dh dec dl cpi dl ,0 brne scan_display_2 ldi dh ,0x01 ldi dl ,0x08 scan_display_3: mov ah ,dh ld al ,Y+ rcall write_word_to_7219_C inc dh dec dl cpi dl ,0 brne scan_display_3 scan_display_end: ret |