[問題] 有關 index addressing
Write a program to get the x value from P1 and send x2 to P2,
continuously.
Solution:
ORG 0
MOV DPTR,#XSQR_TABLE
MOV A,#0FFH
MOV P1,A ;P1 as INPUT PORT
BACK: MOV A,P1 ;GET X
MOVC A,@A+DPTR ;Count the addr.
MOV P2,A ;Issue it to P2
SJMP BACK
ORG 300H
XSQR_TABLE:
DB 0,1,4,9,16,25,36,49,64,81
END
有幾個地方不太明白
1. MOV P1,A 又MOV A,P1 為什麼要做兩次??
2. MOVC A,@A+DPTR 他如果這樣不就變成了 0FFH+0300H? 那A是??
3. MOV P2,A A不就一直不變怎麼跳啊= =?
這學期第一次學組語碰到好多問題~~~頭都快昏了
希望有高手能解答囉^^
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◆ From: 1.174.3.195
推
10/13 06:59, , 1F
10/13 06:59, 1F
→
10/13 06:59, , 2F
10/13 06:59, 2F
→
10/13 09:21, , 3F
10/13 09:21, 3F
→
10/13 09:23, , 4F
10/13 09:23, 4F
→
10/13 09:25, , 5F
10/13 09:25, 5F
→
10/13 09:26, , 6F
10/13 09:26, 6F
了解 謝謝^^ 感覺蠻抽象的
※ 編輯: j5307 來自: 111.254.127.114 (10/15 15:04)
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