清华MSP430课件第3章MSP430指令系统.ppt

JC Label JC LABEL PCold LABEL PCnew offset×2 bytes 注意跳转范围 operation if C=1 then PC+2*offset-PC else execute following instruction following instruction 对 SR 的影响： Status Bits: 不受影响 Mode Bits: OSCOFF,CPUOFF and GIE are not affected JNC Label JNC LABEL PCold LABEL PCnew offset×2 bytes 注意跳转范围 operation if C=0 then PC+2*offset-PC else execute following instruction following instruction 对 SR 的影响： Status Bits: 不受影响 Mode Bits: OSCOFF,CPUOFF and GIE are not affected ;the P1IN.1 signal is used to define or control the program flow BIT #01h , P1IN ;state of signal-carry JC PROGA ;if carry=1 then execute PROGA …… ; else execute here ;R5 is compared to 15 ;if the content is higher or the same, jump to LABEL CMP #15 , R5 JHS LABEL ;if R5=15, then jump to LABEL …… ; else continue here ;jump to LABEL if byte STATUS contain 1 or 0 CMP.B #2 , STATUS JLO LABEL ;if STATUS2 , then jump to LABEL …… ; else continue here ;the result in R6 is added in BUFFER. if an overflow occurs, ;an error handling routine at address ERROR is used ADD R6 , BUFFER ;BUFFER+R6-BUFFER JNC CONT ;no carry, jump to CONT ERROR …… ;error handler start …… CONT …… ;continue with normal program flow …… AND #0AA55h , VAR1 ;mask word addressed by VAR1 ;with AA55h AND.B #0A5h , VAR2 ;mask Lowbyte VAR2 with A5h BIT #0200h , R8 ;bit 9 of R8 set? JNZ TOM ;Yes, branch to TOM …… ;No, proceed BIC #0FC00h , LEO ;Clear 6 MSBs in MEM(LEO) BIC.B #0F8h , LEO ;Clear 5 MSBs in MEM(LEO) BIS #003Fh , TOM ;Set the 6 LSBs in MEM(TOM) BIS.B #0E0h , LEO ;Set the 3 MSBs in MEM(YOM) 与、位测试、位清零、位置 1 指令举例 逻辑异或指令 XOR src , dst XOR.W src , dst XOR.B src , dst operarion: src .XOR. dst dst src 保持不变 dst=src .XOR. dst 对 SR 的影响： Status Bits: N,Z,C,V 将受影响 Mode Bits: OSCOFF,CPUOFF and GIE are not affected10100101.XOR. exclusive OR 逻辑求反指令 仿真 INV dst INV.W dst INV.B dst operarion: .NOT. dst dst dst=.NOT. dst 对 SR