本帖最后由 andeyqi 于 2018-8-22 11:04 编辑 7 M( G- |4 O8 L( b* g1 O0 ]' j & Z* }& ?; W/ ]0 h. `; G官方的软件包已经包含了SD卡的驱动 [8 ^$ g* k6 Q# K5 tSTM32Cube_FW_F7_V1.9.0\Drivers\BSP\STM32F769I-Discovery\stm32f769i_discovery_sd.c% [* ^" S1 _, o L3 |5 F. d, Y7 }1 | " \6 s K6 l- M5 M 现对主要的函数理解以加深对SDIO的认识，为以后的使用积累经验。 , @1 h# ~$ P& @/ A (, 下载次数: 9) 上传 点击文件名下载附件 2 s+ l# n5 C/ P5 O I8 \" J 根据电路图可知硬件连接上三个数据线，一根命令传输线，一根时钟线，一根SD卡插入检测线。. c& Q, E6 s& l/ m; }; c5 ~& F7 d d% o! M2 @, r1 @# T 0 j. |6 Z& _9 U; d SD_HandleTypeDef uSdHandle;2 p- i1 T1 {& [1 G0 A0 _( p /** 6 B+ @9 V7 p3 U: v+ { * @brief Initializes the SD card device. & D" X" K8 j- |! C; B$ r0 w * @retval SD status * q( j; [* |0 R7 _. Y5 ^ */( b2 j6 `" R3 M$ g% Z5 q4 U3 i uint8_t BSP_SD_Init(void) ) P c& a% A* I{ K) R7 Q8 ^ m/ j uint8_t sd_state = MSD_OK; ( I5 ~4 r5 @: O, g$ w$ G r. l2 w$ ~5 A) c0 V. V# ?( B/ Q /* PLLSAI is dedicated to LCD periph. Do not use it to get 48MHz*/ : Y' g w% H4 C1 m& |7 N7 o. ^# r9 F- \# U: y6 V" n /* uSD device interface configuration */ " ?) q u# H' Q2 ^5 T/ l uSdHandle.Instance = SDMMC2; % b& s+ r2 F! ?: ^& g6 w/ B% e uSdHandle.Init.ClockEdge = SDMMC_CLOCK_EDGE_RISING; 6 p# ^( ?9 _3 O+ h0 _ uSdHandle.Init.ClockBypass = SDMMC_CLOCK_BYPASS_DISABLE;) k+ m; E& ^0 R1 d- w# s uSdHandle.Init.ClockPowerSave = SDMMC_CLOCK_POWER_SAVE_DISABLE; ' F! |+ o/ l( c: g. c P uSdHandle.Init.BusWide = SDMMC_BUS_WIDE_1B; . n" |- K) K+ q$ \8 G5 c9 y5 u uSdHandle.Init.HardwareFlowControl = SDMMC_HARDWARE_FLOW_CONTROL_DISABLE; * f% W5 C% k1 l& f1 w uSdHandle.Init.ClockDiv = SDMMC_TRANSFER_CLK_DIV;$ X& p( f! m! @3 J: G8 { L" D 3 w" J/ `) h9 a v7 x( p /* Msp SD Detect pin initialization */ 1 ]0 P6 ]) T2 ?! Q+ C BSP_SD_Detect_MspInit(&uSdHandle, NULL); : F( d/ j& v) N if(BSP_SD_IsDetected() != SD_PRESENT) /* Check if SD card is present */ ; c4 X u$ T- G4 ?3 K) ^. T {+ ^' z, Q2 t' P return MSD_ERROR_SD_NOT_PRESENT;- i: O) Z1 s' n. ? }% H# g- I" ] G7 N& L; i) c ( [% N8 S6 k1 u /* Msp SD initialization */6 |, ?5 p# @0 @: h2 s BSP_SD_MspInit(&uSdHandle, NULL);# W% c3 Y/ n8 h' f" ^; m! f 2 Y% l9 }' W2 T% G1 ` /* HAL SD initialization */1 m1 p% I8 t9 D7 K2 g if(HAL_SD_Init(&uSdHandle) != HAL_OK), }* F7 y8 A# ` { 6 J5 k( ~% e, e sd_state = MSD_ERROR; 4 U, e5 i. j5 P( O$ V }0 s! q' X( J% D! K$ F" k & Z0 \' h( T& d2 ^: l) l; M /* Configure SD Bus width */, F, o7 j3 ?. P if(sd_state == MSD_OK)- m& ]7 @" P" G( ~& @% p P { 5 s, S- E$ R- J* n3 d8 ]7 B# V /* Enable wide operation */( f% w2 J3 H2 d if(HAL_SD_ConfigWideBusOperation(&uSdHandle, SDMMC_BUS_WIDE_4B) != HAL_OK) $ e- @" Y. t# V3 o7 w { & o; u- @/ [# u/ B% ]/ m, _ sd_state = MSD_ERROR; ! [) t" T7 c* A; B1 n+ r) C! X7 ] } 2 Y. G3 h- o! J else" v/ r) k6 f6 q% F7 q { 3 G6 h4 N" Y' S& m4 c j# L; V sd_state = MSD_OK; + ~3 q3 M9 C; ~. c: o# {. A } 6 S$ m6 r1 o5 J3 k3 m }( f& M: N+ _0 o5 g" q return sd_state;* Q% `4 o" j5 U3 O- o }复制代码 u* S2 _. y( _& `- d 代码初始化时设置数据位宽为SDMMC_BUS_WIDE_1B，之后又设置为SDMMC_BUS_WIDE_4B，为什么不一开始就设置成4位，而且硬件原理图上也是按照4位模式接的，后来在编程手册上找到如下描述，需要初始化完成之后再设置位宽度，但是还是没有想明白为什么这么设计。 P, l8 B) J( o. N5 f+ T& _ 8 X& O$ W3 D. W+ tBy default SDMMC_D0 is used for data transfer. After initialization, the host can change the databus width. " _& c) e! x6 n3 @# d + o, ^' l1 g& U8 QBSP_SD_IsDetected()函数根据代码注释和内容可判断是，检测SD卡是否插入,检测到低电平是代表SD卡已插入。/** 6 D, m3 {2 ]) r* z$ | F0 D6 \) U * @brief Detects if SD card is correctly plugged in the memory slot or not. / i% @1 H' S; |$ B. p7 o * @retval Returns if SD is detected or not7 N% H. t5 p. q" `+ s, V: ? */4 T/ Q" D C; a/ o( c uint8_t BSP_SD_IsDetected(void) 0 y: `; J: h* J{" o' `. u/ |7 i: _+ R* b4 J% i __IO uint8_t status = SD_PRESENT;# i3 c- D4 E/ z$ |4 g% V ; {% s/ \6 b% s+ a, b /* Check SD card detect pin */# {: G: g: a' `8 k9 M' i if (HAL_GPIO_ReadPin(SD_DETECT_GPIO_PORT, SD_DETECT_PIN) == GPIO_PIN_SET) : m+ T9 U @$ i! d8 e3 b- [% l3 L8 J {! O$ R4 Z$ g R! ? status = SD_NOT_PRESENT;" C( ]- ?( B& f: B3 ]- y8 N' t }6 ? V, y* h9 z7 @1 v& a& ]3 r : f, t( y0 ? [; Y( s9 |1 Y return status;+ p' I+ G1 L1 z0 J$ ` | }复制代码) X: g# D* v+ h( X( U BSP_SD_Detect_MspInit(&uSdHandle, NULL); 配置sd卡插入检测引脚为输入上拉模式/** # n/ t: y. B& Z. v m& Z% p- Y * @brief Initializes the SD Detect pin MSP. & X9 P, t, K) o! M7 t& g, } * @param hsd: SD handle 3 W/ q, H. i; Y9 N- V8 A * @param Params : pointer on additional configuration parameters, can be NULL. $ _, u Q* T5 j6 p3 H2 S* S# ` * @retval None2 E ?) l% d% @ */ 1 v! T5 A& C. ]. z! G' L: E& p__weak void BSP_SD_Detect_MspInit(SD_HandleTypeDef *hsd, void *Params)8 ^3 B' M G& k/ L) I! _) h- G4 R { ! w7 Z2 i, T1 W) y2 j; j GPIO_InitTypeDef gpio_init_structure; . t3 A1 W" u7 C6 M: [) W9 s; M, O6 _1 e SD_DETECT_GPIO_CLK_ENABLE();6 D6 G8 W0 k; W4 C+ v: f/ i# I5 r" c 1 c2 b/ ~4 k7 {. f5 ^# |' p9 m /* GPIO configuration in input for uSD_Detect signal */) A: J3 O4 j# ? gpio_init_structure.Pin = SD_DETECT_PIN;/ M' d' K) u* C gpio_init_structure.Mode = GPIO_MODE_INPUT; d5 x9 `& {) T4 W: z/ h$ i gpio_init_structure.Pull = GPIO_PULLUP; 1 b1 J( S* o4 ~5 Y gpio_init_structure.Speed = GPIO_SPEED_HIGH; 6 o! ^) F6 H* F4 r( Z HAL_GPIO_Init(SD_DETECT_GPIO_PORT, &gpio_init_structure);. g. L' d; x# T( V }复制代码/** / K! ^6 A" ^4 b * @brief Initializes the SD Card./ F* T; x. @/ C1 l4 F& I% u! O1 _ * @param hsd Pointer to SD handle% _2 ?, B" p7 }; y' L * @note This function initializes the SD card. It could be used when a card 9 A6 A6 ]- B! |7 B `+ K: { re-initialization is needed. ( r0 b' R" F# g/ B B: ?0 d$ S7 T * @retval HAL status 3 E1 M; F' u. j; G) ?4 X */ # w. U6 h) J' r( j! H3 FHAL_StatusTypeDef HAL_SD_InitCard(SD_HandleTypeDef *hsd) # v% [/ s, Q+ b4 X8 o5 K; ?5 y8 V, {7 x{ . l7 L- ^( n7 B1 K$ V uint32_t errorstate = HAL_SD_ERROR_NONE; 1 {6 J( y, k- ~, g5 @1 f SD_InitTypeDef Init; * ]! I1 x. j$ I1 B, F1 _ " ?) z: Y- S" I, B. u/ H" ]6 x) w5 e /* Default SDMMC peripheral configuration for SD card initialization */. H* @8 y. }5 H: I e p3 F Init.ClockEdge = SDMMC_CLOCK_EDGE_RISING;+ X4 ~5 D6 r- ]1 q( t2 z. c Init.ClockBypass = SDMMC_CLOCK_BYPASS_DISABLE; . f X. H% H8 ^5 |5 |4 X& B8 Z Init.ClockPowerSave = SDMMC_CLOCK_POWER_SAVE_DISABLE; 8 i. Z( K7 |3 O+ k+ O, h; O" ]7 G Init.BusWide = SDMMC_BUS_WIDE_1B; $ X0 m' X0 M, `0 o0 W7 f3 C+ p Init.HardwareFlowControl = SDMMC_HARDWARE_FLOW_CONTROL_DISABLE;+ X9 E1 G: k2 l Init.ClockDiv = SDMMC_INIT_CLK_DIV;' m( z1 s! [5 W: L6 \$ {* z# c $ |. P% U9 Z. O2 g# \% U+ d: ^) h /* Initialize SDMMC peripheral interface with default configuration */+ w; J* ?" H E" \1 i* ]: \/ Z SDMMC_Init(hsd->Instance, Init); 8 b0 }' _8 \2 B# @" i7 P! i$ z& D" |$ _- x- ] e /* Disable SDMMC Clock */ % c3 F! Y2 B$ d4 d" }( ?. X __HAL_SD_DISABLE(hsd); , T6 E8 l! i. h6 e! u l' ~ ! M: q' p- X4 G2 U /* Set Power State to ON */ ' W9 H+ z: F) }; R2 X: J/ ` SDMMC_PowerState_ON(hsd->Instance);# \# M# w" p! B 3 g. v# @* ?8 [( q8 D /* Enable SDMMC Clock */& p, Z9 V- | v' R6 y# { __HAL_SD_ENABLE(hsd); F8 D0 T, _/ E g4 N1 a8 E" ]8 D$ n8 ^1 j0 b /* Required power up waiting time before starting the SD initialization sequence */ 8 ~% Z/ r; u6 |* w& C& c HAL_Delay(2); # t1 s' N5 b. a. f$ n ! W' J2 y3 E8 K" `; C /* Identify card operating voltage */ * j2 v" Z3 u. W7 Z. u$ q2 e errorstate = SD_PowerON(hsd); + q- I# q6 b$ P7 B3 ^" \- { if(errorstate != HAL_SD_ERROR_NONE) ! i3 y" F# X5 M { + H) {: Y# X4 C- G) [7 L! e4 X hsd->State = HAL_SD_STATE_READY;% ]; J/ S. ~0 O# M, O, c hsd->ErrorCode |= errorstate;, J( `* l4 Y! p2 X return HAL_ERROR; # h5 f) s8 P: f% L: y" A+ a } 0 x. A+ X& x7 I8 V" W: x* L+ Z3 X /* Card initialization */8 z& F9 ]( J; e. [ errorstate = SD_InitCard(hsd);! U4 J& J% ~4 q1 Z* f if(errorstate != HAL_SD_ERROR_NONE)+ s7 C* x }, C" S/ C5 A( D) r {+ |7 i/ |+ M/ D* C; i( h) M: t hsd->State = HAL_SD_STATE_READY;) U. G2 l) D$ g hsd->ErrorCode |= errorstate; 6 [& I. R* J2 @) ` return HAL_ERROR;& j7 M4 M. \- a- i8 o" P } ( M. a# e4 d& z0 C8 i6 b: h; ^, A' g' z/ ]3 C& k+ B return HAL_OK; ( Q; F. [; {5 v}复制代码 d; t+ V2 i3 u# X 3 ]5 s+ J+ U# F! H/ j$ | ( S( ]; {* y7 Q2 R, T
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