;;入口:第1、2、3次采集數據位次存于R1、R2、R3,
;;出口:比較所得中值數據存于R0,
Filter_C:
PUSH PSW
MOV A, R1
CLR C
SUBB A, R2 ;;R1與R2作相減
JNC LP1 ;;若R1≧R2,不交換
MOV A, R1 ;;若R1<R2, 交換
XCH A, R2
MOV R1, A
LP1:
MOV A, R3
CLR C
SUBB A, R1
JNC LP3
MOV A, R3
CLR C
SUBB A, R2
JNC LP4
MOV A, R2
MOV R0, A
AJMP Filish
LP3:
MOV, A, R1
MOV R0, A
AJMP FILISH:
LP4:
MOV A, R3
MOV R0, A
FILISH:
POP PSW
RET
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