http:\/\/www.waveshare.net\/study\/article-645-1.html<\/a><\/p>\n\u5fae\u96ea\u7528\u7684\u662f\u786c\u4ef6 USART + DMA\uff0c\u4e0d\u8fc7\u9053\u7406\u662f\u4e00\u6837\u7684\u561b\uff0c\u62ff\u6765\u53c2\u8003\u5c31\u662f\u3002<\/p>\n
<\/p>\n
\u9996\u5148\u628a\u540c\u6b65\u963b\u585e\u5f0f\u7a0b\u5e8f\u5199\u597d\uff0c\u786e\u8ba4\u6db2\u6676\u5c4f\u53ef\u4ee5\u7528\u4e86\u3002\u76f4\u63a5\u4e0a\u5f02\u6b65\u975e\u963b\u585e\u7684\u65b9\u5f0f\u6015\u662f\u5c4f\u4e0d\u4eae\u90fd\u641e\u4e0d\u6e05\u662f\u901a\u8baf\u9519\u4e86\u8fd8\u662f\u6307\u4ee4\u9519\u4e86\u2026\u2026<\/p>\n
\u7136\u540e\u5728Cube\u4e2d\u5f00\u542f I2C2 \u7684 DMA\uff0c\u5728 Configuration \u4e2d\u6253\u5f00 I2C \u914d\u7f6e\u7a97\u53e3\uff0c\u6dfb\u52a0 DMA Request\uff0c\u5206\u4e3a I2C_TX \u548c I2C_RX \u4e24\u79cd Request\uff0c\u8fd9\u91cc\u53ea\u9700\u8981\u53d1\u9001\u7684\u3002\u53c2\u6570\u7684\u8bdd\uff0c\u4f18\u5148\u7ea7\u9002\u5f53\u8c03\u6574\u4e00\u4e0b\uff0c\u5176\u4ed6\u9ed8\u8ba4\u5c31\u53ef\u4ee5\u4e86\uff0c\u5177\u4f53\u53c2\u6570\u7684\u542b\u4e49\u770b\u624b\u518c\u6216\u5fae\u96ea\u7684\u90a3\u7bc7\u6587\u7ae0\u3002<\/p>\n
\u4e00\u5b9a\u8bb0\u5f97\u6253\u5f00 I2C \u7684\u4e2d\u65ad\uff0c\u5426\u5219\u4f60\u53ea\u80fd\u8fdb\u884c\u4e00\u6b21\u4e0d\u8d85\u8fc7 256 Bytes \u7684 DMA\uff0c\u4e4b\u540e\u5c31\u5f97\u624b\u52a8\u53bb\u6e05\u7a7a\u6807\u5fd7\u4f4d\uff0c\u518d\u624b\u52a8\u542f\u52a8\u4e00\u6b21 DMA \u53d1\u9001\u3002<\/p>\n
\u73b0\u5728\u53ef\u4ee5\u91cd\u65b0\u751f\u6210\u4ee3\u7801\u4e86\uff0c\u56de\u5230\u4ee3\u7801\uff0c\u4e0d\u8003\u8651\u9519\u8bef\u5904\u7406\u7684\u8bdd\uff0c\u628a\u539f\u6765\u7684 I2C \u51fd\u6570\u6362\u6210 DMA \u7248\u672c\uff0c\u5c31\u53ef\u4ee5\u76f4\u63a5\u4f7f\u7528\u4e86\uff0c\u662f\u4e0d\u662f\u5f88\u65b9\u4fbf\uff08\u7b11\u2014\u2014\uff09<\/p>\n
\u53e6\u5916\uff0c\u8fd8\u5efa\u8bae\u5f00\u542f I2C \u7684\u9519\u8bef\u4e2d\u65ad\u3002\u56e0\u4e3a\u662f\u5f02\u6b65\u64cd\u4f5c\u561b\uff0c\u542f\u52a8 DMA \u7684\u65f6\u5019\u53ea\u4f1a\u544a\u8bc9\u4f60\u8bbe\u5907\u662f\u5426\u7a7a\u95f2\uff0c\u7136\u540e CPU \u5c31\u5e72\u522b\u7684\u53bb\u4e86\u3002\u81f3\u4e8e\u4f20\u8f93\u662f\u5426\u6210\u529f\uff0c\u6709\u6ca1\u6709\u9519\u8bef\uff0c\u662f\u4e0d\u77e5\u9053\u7684\uff0c\u53ea\u6709\u5728\u9519\u8bef\u53d1\u751f\u4e4b\u540e\uff0c\u901a\u8fc7\u4e2d\u65ad\u7684\u65b9\u5f0f\u8c03\u7528\u4f60\u6ce8\u518c\u7684\u56de\u6389\u51fd\u6570\u6765\u62a5\u544a\u9519\u8bef\u3002<\/p>\n
\uff08=======================\u8865\u5145=============================\uff09<\/p>\n
\u5728 stm32l4xx_hal_i2c.c \u4e2d\u53ef\u4ee5\u627e\u5230\u5982\u4e0b\u51fd\u6570\u5b9a\u4e49\uff1a<\/p>\n
\/**\n * @brief Memory Tx Transfer completed callback.\n * @param hi2c Pointer to a I2C_HandleTypeDef structure that contains\n * the configuration information for the specified I2C.\n * @retval None\n *\/\n__weak void HAL_I2C_MemTxCpltCallback(I2C_HandleTypeDef *hi2c)\n{\n \/* Prevent unused argument(s) compilation warning *\/\n UNUSED(hi2c);\n\n \/* NOTE : This function should not be modified, when the callback is needed,\n the HAL_I2C_MemTxCpltCallback could be implemented in the user file\n *\/\n}<\/pre>\n\u8fd9\u4e2a\u5c31\u662f HAL_I2C_Mem_Write_DMA \u548c HAL_I2C_Mem_Write_IT \u7684\u56de\u8c03\u51fd\u6570\uff0c\u5f53\u4e4b\u524d I2C \u4e0a\u7684\u5f02\u6b65 IO \u64cd\u4f5c\u5b8c\u6210\u540e\uff0c\u7cfb\u7edf\u5c06\u8c03\u7528\u8fd9\u4e2a\u51fd\u6570\u6765\u544a\u8bc9\u4f60\u4e0a\u4e00\u6b21\u64cd\u4f5c\u5df2\u5b8c\u6210\u3002\u540c\u7406\uff0c\u5f02\u6b65\u64cd\u4f5c\u53d1\u751f\u9519\u8bef\u65f6\u7684\u56de\u6389\u51fd\u6570\u4e5f\u5728\u6b64\u5904\u3002<\/p>\n
\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u8fd9\u91cc\u7684 HAL_I2C_MemTxCpltCallback \u7684\u56de\u8c03\u51fd\u6570\u548c\u00a0I2C2_EV_IRQHandler \u7684\u4e2d\u65ad\u670d\u52a1\u51fd\u6570\u610f\u4e49\u6709\u6240\u4e0d\u540c\uff0c\u524d\u8005\u5728\u51fd\u6570\u5c01\u88c5\u4e0a\u8981\u66f4\u9ad8\u4e00\u5c42\u3002<\/p>\n
\u5f53\u8c03\u7528\u00a0HAL_I2C_Mem_Write_DMA \u8fd9\u4e2a\u51fd\u6570\u65f6\uff0c\u662f\u8c03\u7528\u7684 HAL \u7684\u63a5\u53e3\uff0c\u5e76\u5c06 CPU \u4ea4\u7ed9 HAL\uff0c\u7136\u540e\u7531 HAL \u914d\u7f6e\u5916\u8bbe\uff0c\u5e76\u542f\u52a8 DMA \u4f20\u8f93\uff0c\u7136\u540e\u91ca\u653e CPU\u3002\u4e00\u6b21 DMA \u4f20\u8f93\u7ed3\u675f\u540e\uff0c\u4e2d\u65ad\u89e6\u53d1 I2C2_EV_IRQHandler\uff0c\u8fd9\u4e2a\u51fd\u6570\u68c0\u67e5\u5177\u4f53\u7684\u4e2d\u65ad\u4e8b\u4ef6\uff0c\u7136\u540e\u628a CPU \u79fb\u4ea4\u7ed9 HAL\u3002HAL \u5224\u65ad\u672c\u6b21 DMA \u662f\u5426\u4f20\u5b8c\u4e86\u7528\u6237\u63d0\u4ea4\u7684\u5168\u90e8\u6570\u636e\uff0c\u5982\u679c\u672a\u4f20\u5b8c\uff0c\u5219\u542f\u52a8\u4e0b\u4e00\u6b21 DMA\uff1b\u5982\u679c\u5df2\u4f20\u5b8c\uff0c\u5219\u8c03\u7528 HAL_I2C_MemTxCpltCallback\uff0c \u5c06 CPU \u4ea4\u7ed9\u7528\u6237\uff0c\u4ee3\u8868 HAL \u5df2\u7ecf\u6267\u884c\u5b8c\u8fd9\u6b21\u7684\u6570\u636e\u53d1\u9001\u8bf7\u6c42\u3002<\/p>\n
\u5373\uff0c\u4e00\u6b21 HAL_I2C_Mem_Write_DMA \uff08\u6216\u8005_IT\uff09\u53ea\u4f1a\u89e6\u53d1\u4e00\u6b21\u00a0HAL_I2C_MemTxCpltCallback\uff0c\u4f46\u89c6\u957f\u5ea6\u800c\u5b9a\uff0c\u53ef\u80fd\u4f1a\u591a\u6b21\u89e6\u53d1 I2C \u4e2d\u65ad\u548c DMA \u4e2d\u65ad\u3002<\/p>\n
\u55ef\uff0c\u6ca1\u597d\u597d\u8bfb Cube \u7684\u624b\u518c\uff0c\u8fd9\u95ee\u9898\u5934\u75bc\u4e86\u597d\u4e45\u3002<\/p>\n
\u53e6\u5916\u8fd8\u6709\u4e00\u70b9\u5c31\u662f\uff0c\u8981\u6ce8\u610f\u540c\u6b65\u95ee\u9898\u3002\u50cf\u4ee5\u4e0b\u4ee3\u7801\u662f\u975e\u5e38\u5371\u9669\u7684\uff1a<\/p>\n
void sendSomething() {\n char ch[] = \"LoveLive!\"; \/\/ \u65b0\u5efa\u4e34\u65f6\u53d8\u91cf\uff08\u61d2\u7684\u6253\u6210\u90a3\u6837\u5b50\u4e86\uff0c\u610f\u4f1a\u610f\u4f1a\uff09\n HAL_I2C_Mem_Write_DMA(&hi2c2, 0x78, 0x80, 1, &ch, 10); \/\/ \u542f\u52a8\u4e86\u4e00\u6b21\u53d1\u9001\n} \/\/ \u64a4\u9500\u4e86\u4e34\u65f6\u53d8\u91cf<\/pre>\n\u60f3\u60f3\u770b\uff1f\u7531\u4e8e\u53d8\u91cf\u5df2\u7ecf\u88ab\u91ca\u653e\u4e86\uff0c\u5982\u679c\u975e\u5e38\u4e0d\u5e78\u4f60\u7684\u7a0b\u5e8f\u6070\u597d\u5728\u8fd9\u6bb5\u5185\u5b58\u91cc\u5199\u4e86\u65b0\u7684\u5185\u5bb9\uff0cI2C\u4f1a\u53d1\u51fa\u53bb\u4ec0\u4e48\u4e1c\u897f\uff1f<\/p>\n
\u5982\u679c\u4f7f\u7528\u6307\u9488\u7684\u8bdd\uff0c\u6211\u8be5\u4ec0\u4e48\u65f6\u5019\u91ca\u653e\uff1f\u6211\u8be5\u91ca\u653e\u54ea\u4e00\u4e2a\u6307\u9488\uff1f\u8fd9\u6837\u505a\u4f1a\u4e0d\u4f1a\u5185\u5b58\u6cc4\u9732\uff1f<\/p>\n
\u6240\u4ee5\u8bf4\uff0c\u8fd8\u633a\u6298\u817e\u7684\u3002\u4e0d\u8fc7\u597d\u5728\u6682\u65f6\u8fd8\u4e0d\u7528\u8003\u8651\u8fd9\u4e48\u591a\uff0c\u7b49\u4e4b\u540e\u6162\u6162\u6765\u5427~<\/p>\n
OK\uff0c\u63a5\u4e0b\u6765\u8be5\u7814\u7a76\u5355\u7247\u673a\u7684\u5b57\u5e93\u95ee\u9898\u4e86\uff5e\u2606\u5f61<\/p>\n","protected":false},"excerpt":{"rendered":"
\u7531\u4e8e\u9879\u76ee\u4e0d\u5141\u8bb8\u963b\u585e\u7684\u6db2\u6676\u5c4f I\/O \u64cd\u4f5c\uff0c\u56e0\u6b64\u9700\u8981\u4f7f\u7528\u786c\u4ef6 I2C + DMA \u6765\u8fdb\u884c\u3002\u5176\u5b9e\u4e2d\u65ad\u65b9\u5f0f\u4e5f\u53ef\u4ee5\uff0c\u4e0d … <\/p>\n
\u7ee7\u7eed\u9605\u8bfb\u201c\u4f7f\u7528\u786c\u4ef6 I2C + DMA \u64cd\u4f5c\u6db2\u6676\u5c4f (STM32)\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[1],"tags":[],"class_list":["post-299","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p83CFH-4P","_links":{"self":[{"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=\/wp\/v2\/posts\/299","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=299"}],"version-history":[{"count":2,"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=\/wp\/v2\/posts\/299\/revisions"}],"predecessor-version":[{"id":317,"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=\/wp\/v2\/posts\/299\/revisions\/317"}],"wp:attachment":[{"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=299"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=299"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/himmel.tech\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=299"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}