ZHCU032K December 2004 – August 2022 MSP430AFE221 , MSP430AFE222 , MSP430AFE223 , MSP430AFE231 , MSP430AFE232 , MSP430AFE233 , MSP430AFE251 , MSP430AFE252 , MSP430AFE253 , MSP430F2001 , MSP430F2002 , MSP430F2003 , MSP430F2011 , MSP430F2012 , MSP430F2013 , MSP430F2101 , MSP430F2111 , MSP430F2112 , MSP430F2121 , MSP430F2122 , MSP430F2131 , MSP430F2132 , MSP430F2132-EP , MSP430F2232 , MSP430F2234 , MSP430F2252 , MSP430F2252-Q1 , MSP430F2254 , MSP430F2272 , MSP430F2272-Q1 , MSP430F2274 , MSP430F2274-EP , MSP430F233 , MSP430F2330 , MSP430F235 , MSP430F2350 , MSP430F2370 , MSP430F2410 , MSP430F2416 , MSP430F2417 , MSP430F2418 , MSP430F2419 , MSP430F247 , MSP430F2471 , MSP430F248 , MSP430F2481 , MSP430F249 , MSP430F2491 , MSP430F2616 , MSP430F2617 , MSP430F2618 , MSP430F2619 , MSP430G2001 , MSP430G2101 , MSP430G2102 , MSP430G2111 , MSP430G2112 , MSP430G2121 , MSP430G2131 , MSP430G2132 , MSP430G2152 , MSP430G2153 , MSP430G2201 , MSP430G2201-Q1 , MSP430G2202 , MSP430G2203 , MSP430G2210 , MSP430G2211 , MSP430G2212 , MSP430G2213 , MSP430G2221 , MSP430G2230 , MSP430G2231 , MSP430G2231-Q1 , MSP430G2232 , MSP430G2233 , MSP430G2252 , MSP430G2253 , MSP430G2302 , MSP430G2303 , MSP430G2312 , MSP430G2313 , MSP430G2332 , MSP430G2333 , MSP430G2352 , MSP430G2353 , MSP430G2402 , MSP430G2403 , MSP430G2412 , MSP430G2413 , MSP430G2432 , MSP430G2433 , MSP430G2444 , MSP430G2452 , MSP430G2453 , MSP430G2513 , MSP430G2533 , MSP430G2544 , MSP430G2553 , MSP430G2744 , MSP430G2755 , MSP430G2855 , MSP430G2955 , MSP430TCH5E
任何擦除周期都可从 RAM 发起。在这种情况下,CPU 不会被占用,可以继续执行 RAM 中的代码。必须首先轮询 BUSY 位以确定擦除周期已结束,然后 CPU 才能再次访问任何闪存地址。如果在 BUSY = 1 时发生闪存访问,则发生访问违例,会设置 ACCVIFG,擦除结果是不可预测的。
图 7-6 展示了从 RAM 启动擦除的流程。
; Segment Erase from RAM.514 kHz < SMCLK < 952 kHz
; Assumes ACCVIE = NMIIE = OFIE = 0.
MOV #WDTPW+WDTHOLD,&WDTCTL ; Disable WDT
L1 BIT #BUSY, &FCTL3 ; Test BUSY
JNZ L1 ; Loop while busy
MOV #FWKEY+FSSEL1+FN0, &FCTL2 ; SMCLK/2
MOV #FWKEY&FCTL3 ; Clear LOCK
MOV #FWKEY+ERASE, &FCTL1 ; Enable erase
CLR &0FC10h ; Dummy write, erase S1
L2 BIT #BUSY, &FCTL3 ; Test BUSY
JNZ L2 ; Loop while busy
MOV #FWKEY+LOCK&FCTL3 ; Done, set LOCK
... ; Re-enable WDT?