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??<br />下面是程序,麻烦高手指点一下!!(用的是AVR单片机)<br />scan_display: <br /> ldiw yl ,yh,display_led_buff ; 送显示地址<br /> ldi dh ,0x01 ; 数码管1的高字节<br /> ldi dl ,0x08 ; 8个数码管<br />scan_display_1:<br /> mov ah ,dh ; 高字节<br /> ld al ,Y+ ; 低字节<br /> rcall write_word_to_7219_A ; 写入A<br /> inc dh<br /> dec dl<br /> cpi dl ,0<br /> brne scan_display_1<br /> <br /> ldiw yl ,yh,display_led_buff+8<br /> ldi dh ,0x01<br /> ldi dl ,0x08<br />scan_display_2:<br /> mov ah ,dh<br /> ld al ,Y+<br /> rcall write_word_to_7219_B<br /> inc dh<br /> dec dl<br /> cpi dl ,0<br /> brne scan_display_2<br /> <br /> ldi dh ,0x01<br /> ldi dl ,0x08<br />scan_display_3:<br /> mov ah ,dh<br /> ld al ,Y+<br /> rcall write_word_to_7219_C<br /> inc dh<br /> dec dl<br /> cpi dl ,0<br /> brne scan_display_3<br />scan_display_end:<br /> ret |
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