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
默认的 DMA 通道优先级是 DMA0-DMA1-DMA2。如果两个或三个触发同时发生或者挂起,拥有最高优先级的通道将会首先完成传输(单次,块或者突发块传输),然后是第二优先级的通道,最后是第三优先级的通道。如果一个较高优先级的通道被触发,进行中的传输中将不会被暂停。一直到进行中的传输完成后较高优先级的传输才开始。
DMA 通道的优先级由 ROUNDROBIN 位配置。当 ROUNDROBIN 位被置位时,完成一个传输的通道的优先级会变为最低。通道的优先级的顺序总保持相同,DMA0-DMA1-DMA2(请参阅表 6-3)。
DMA 优先级 | 传输发生 | 新的 DMA 优先级 |
---|---|---|
DMA0 - DMA1 - DMA2 | DMA1 | DMA2 - DMA0 - DMA1 |
DMA2 - DMA0 - DMA1 | DMA2 | DMA0 - DMA1 - DMA2 |
DMA0 - DMA1 - DMA2 | DMA0 | DMA1 - DMA2 - DMA0 |
当 ROUNDROBIN 位被清零时,通道的优先级回到默认优先级。