在使用1.2版本的HAL库开发STM32H743的串口7设备的时候,遇到了如下问题:' d: }# l( G4 M
数据发送使用HAL_UART_Transmit进行发送,单独测试发送的时候,发送正常。* b( V+ b: c3 [- h0 n
接收则是HAL_UART_Receive_IT,逐字节进行接收并存放至数组,配合定时器进行不定长数据接收,单独测试接收的时候,接收也正常。
5 g" ]2 k! Z4 q) E* h; C: O然后博主这里就把TX和RX短接,按理说在发送完成后的50ms以内就会打印接收到的数据(定时器设置的50ms溢出,即不定长数据间隔为50ms),但是这里并没有看到输出。
9 B) A2 X- L' e! i$ E4 F% ]7 k/ c. E" B" x' ?
研究了下源码,可以发现,发送的时候,会把串口状态huart->gState标记为发送忙HAL_UART_STATE_BUSY_TX并上锁。
5 s# [& A" d. D- HAL_StatusTypeDef HAL_UART_Transmit(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)2 a2 {2 U9 p* b0 ^
- {
9 r6 {2 i6 P& H# e( L B! A - uint16_t* tmp;
% n! h( h% L+ h$ C% R( z6 @ - uint32_t tickstart = 0U;
; `. X& ]3 a8 ?+ Q/ |! q8 ~5 C - 5 t C# k- v6 a. Z+ x; |
- /* Check that a Tx process is not already ongoing */
: x4 ^& D. {; H1 ^ - if(huart->gState == HAL_UART_STATE_READY)
* ^4 h. h$ Y' \- f& q - {) _, I n3 V+ b4 ]
- if((pData == NULL ) || (Size == 0U))
# o, d; R* `) r0 d; k - {
$ L( r7 [/ ^0 w! e - return HAL_ERROR; c3 {$ t, o5 x. G. `% c ?
- }' R B0 r$ D2 Q, l, C
! y( v( P: N( ?- /* Process Locked */7 \( ^* p7 F+ K- }' o# i! Q
- __HAL_LOCK(huart);* E: a/ @6 S7 v0 y( Z |
- 3 g6 D% o1 k* p0 E! N5 b
- huart->ErrorCode = HAL_UART_ERROR_NONE;* P. Q- ]! F# m; v) A. j: R% _
- huart->gState = HAL_UART_STATE_BUSY_TX;
7 U0 a2 d/ S& H1 i
) |: L4 D9 g3 p, B' B+ F% \- /* Init tickstart for timeout managment*/
) _. x' k( |& I8 T' g9 o* A. K - tickstart = HAL_GetTick();
% |% G" h3 ?6 C. h' d: l4 X
. }+ r0 t3 q; A; b- j- huart->TxXferSize = Size;
6 T- G4 c- l" _1 A8 x - huart->TxXferCount = Size;5 ~: j1 C$ t* o1 _) {' G
- while(huart->TxXferCount > 0U)/ N1 I* _+ K8 {$ L* {
- {
1 C5 d$ @0 t, Z: C - huart->TxXferCount--;
! ^& m" P$ N6 P" S$ X- i3 N - if(UART_WaitOnFlagUntilTimeout(huart, UART_FLAG_TXE, RESET, tickstart, Timeout) != HAL_OK)5 A2 z6 L. h/ I* M' z( d3 [
- {, S. a6 z3 Z) @8 g; N- T$ _# y, N2 v
- return HAL_TIMEOUT;$ m% X9 V& j- ]. p0 o L
- }$ q9 p4 T5 L+ _' [4 k6 Q
- if ((huart->Init.WordLength == UART_WORDLENGTH_9B) && (huart->Init.Parity == UART_PARITY_NONE))
+ t' @7 l1 E& S+ ?: y - {
/ T3 ^4 b5 X; |/ |& Y - tmp = (uint16_t*) pData;$ w# W) y+ R$ T5 p" s, O+ S" n5 r3 ?
- huart->Instance->TDR = (*tmp & (uint16_t)0x01FFU);
. J% a2 C7 s# {/ j - pData += 2U;
( R5 n' ~* r0 N. ?- L9 _ r; O - }5 F# C: _* E$ P+ H8 R3 w5 f
- else7 L: Z, [$ d! A: s" |. {
- {& r2 s0 k3 P1 I O- h9 Y6 D: [. J) E
- huart->Instance->TDR = (*pData++ & (uint8_t)0xFFU);
0 w* Y2 i- i( e$ ~4 D: u# P - }9 Y, n6 r9 P6 f2 l; Y
- }0 P1 q0 Z% O; F) Q
- if(UART_WaitOnFlagUntilTimeout(huart, UART_FLAG_TC, RESET, tickstart, Timeout) != HAL_OK)
3 I7 K1 C# P9 j( d - {$ X X8 \' s: X
- return HAL_TIMEOUT;
3 S5 s' T E6 g. _ - }, E1 d- x+ I2 n2 A) f) w0 l- s) \$ Q; G
- X* n! w# D0 Y- /* At end of Tx process, restore huart->gState to Ready */4 V2 q3 z y2 s: w/ c: ~( S
- huart->gState = HAL_UART_STATE_READY;# J3 M' g5 c; s9 z
3 S6 P9 o" e4 \( m2 V- /* Process Unlocked */
5 G2 Z+ W6 m x; U' o - __HAL_UNLOCK(huart);1 K y% Y2 V7 l: g3 j! c8 }
- 1 O* X9 c: U+ F6 t3 s
- return HAL_OK;: l$ @" p0 C- D' w+ e
- }
8 A: V6 K {6 T* F4 l, w3 P; c# x - else _3 { c+ {( W* Q) R
- {
3 J" Z- D, |+ I2 N4 v. x2 ? - return HAL_BUSY;
7 S+ f t# @4 w$ i8 \# j - }0 c0 ]+ [3 p: e9 S; i: g
- } d# L2 ]; E, S: G/ |' J3 u- D9 z
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" q$ s: w; F. E* U) C5 U而接收中断触发后,中断向量入口UART7_IRQHandler会直接调用HAL_UART_IRQHandler(&huart7)分析中断请求,根据接收数据完成请求函数调用UART_Receive_IT(huart),注意这里会把huart->RxState设置为准备接收HAL_UART_STATE_READY并上锁。- X& B! e; k. j( F n( s
- HAL_StatusTypeDef HAL_UART_Receive_IT(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size)
$ G5 T1 ]! |+ F8 Z$ Z3 A - {
, N7 @. R' w5 b4 c+ q/ c: ^% a" q - /* Check that a Rx process is not already ongoing */, E7 [5 Z8 \- z$ S) A
- if(huart->RxState == HAL_UART_STATE_READY)
5 w7 h% L6 h( q" S$ N. ^) r/ G" M - {
' o; `9 N# P" y6 K/ L7 J - if((pData == NULL ) || (Size == 0U)): @% K0 H4 z9 o/ Z* Q7 {
- {: k+ O2 D' B5 s) R. K- C/ F
- return HAL_ERROR;4 P0 ]+ d& y8 x$ \) E; K! X
- }
4 n- Z3 v5 n/ b8 p% u: z1 Q Q
+ C k5 j- r1 m L% E/ i/ b9 {- /* Process Locked */+ [ ?3 b3 a8 m2 `, i
- __HAL_LOCK(huart);0 U& Q$ b" Y. @1 Q
2 S( @: C' x( _! P3 a- P/ R- huart->pRxBuffPtr = pData;6 {( y5 T7 Z( N% X3 z# {
- huart->RxXferSize = Size;$ J' l: x' u9 c: l" H( |9 W. A
- huart->RxXferCount = Size;
' r v2 _" p# _$ V
, G, V; i# s& R' |; n, R$ P+ T1 |# I- /* Computation of UART mask to apply to RDR register */
* e+ ^5 y) @$ P6 @: ~7 a - UART_MASK_COMPUTATION(huart); z% @- [8 Z2 `2 `2 P7 n- O
- : `+ |: O0 r+ k$ u+ k2 g4 t
- huart->ErrorCode = HAL_UART_ERROR_NONE;% r; R- T2 O4 E2 [( Q" C! \4 C
- huart->RxState = HAL_UART_STATE_BUSY_RX;( B" v+ h: D$ ?' x& r
- 0 B" m+ m7 _% |- E- b! N2 y8 K q
- /* Process Unlocked */ `5 ]6 q3 }3 S# W9 \
- __HAL_UNLOCK(huart);( m& `7 r+ S: Y
/ I! x7 V# I" W4 M0 G- /* Enable the UART Error Interrupt: (Frame error, noise error, overrun error) */
: B9 ]. E7 t& z. Z2 l - SET_BIT(huart->Instance->CR3, USART_CR3_EIE);+ x* t6 K/ w# U) A. j
- ' g, Q9 l0 V8 F5 m
- /* Enable the UART Parity Error interupt and RX FIFO Threshold interrupt
) z; d2 ^6 x" P3 S - (if FIFO mode is enabled) or Data Register Not Empty interrupt
, V; p# j7 Y8 C! z4 G - (if FIFO mode is disabled).! d( [# X/ U5 F; T4 a
- */
% B0 Y3 h. {# \0 m8 o w - if (READ_BIT(huart->Instance->CR1, USART_CR1_FIFOEN) != RESET)# h) h% L2 R) L* _& W z3 _ S
- {) f" x' O9 A0 E+ G7 @$ t% s) B
- SET_BIT(huart->Instance->CR1, USART_CR1_PEIE);
2 X" g6 s7 X; ~. i6 q+ i5 o6 V - SET_BIT(huart->Instance->CR3, USART_CR3_RXFTIE);
- L# {2 `9 d4 H - }
6 `) ?* Z1 @% B) {# P2 Y - else. e* t2 V/ `: T; k, T0 [( C/ @
- {- `) ^: ], |" W
- SET_BIT(huart->Instance->CR1, USART_CR1_PEIE | USART_CR1_RXNEIE);
1 M2 a/ `8 q9 y' T" w9 o$ O - }! u" G/ L+ d9 q! u
- 0 u. ^# n6 ?+ ^5 L/ C, i6 ^. ^/ H
- return HAL_OK;
* w7 W) {; t! e" |# @- g - }( e$ o& c$ j9 ~+ Q. j/ m
- else4 P" v( R; g1 \1 ]" M. M
- {! K) E3 X3 C: z4 U) n1 v# e
- return HAL_BUSY;( E& p6 x a. S$ x$ W8 q4 l
- }
. c" }5 _2 z' g( h8 o - } v# e/ x5 @5 G) j/ p
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0 |: B7 E4 [+ `4 h' c) |* M; I$ K7 t查看一下定义,可以发现这里的一个设计缺陷,gState代表发送状态,RxState代表接收状态,通过这个状态机来保证接收和发送过程的完整性,但是,只设计了一把锁Lock,而锁是用来保护发送或者接收单个字节的完整性的,这样就导致了在连续发送的过程中,处理接收来的数据发现串口设备被上锁了,返回busy,从而丢失了发送的数据。( J. @. j: v% w" F
- typedef struct0 n" y9 c& R5 U) B/ o* Y% g& g
- {
: g* h" f9 r. Y) t3 B" e0 ^6 H - USART_TypeDef *Instance; /*!< UART registers base address */
# d: q* K- Y: h( V) E9 d - + m# M# U1 Z6 u$ S' B
- UART_InitTypeDef Init; /*!< UART communication parameters */1 `! M, d2 W; [0 X- j3 \, z) ]1 n& m
: C0 ~* U/ H5 [5 q- `5 X1 _- UART_AdvFeatureInitTypeDef AdvancedInit; /*!< UART Advanced Features initialization parameters */
) y9 s" m+ @2 ~& p) w7 c t5 ? C" f, d - & m! d5 }! m1 P8 f! {" x
- uint8_t *pTxBuffPtr; /*!< Pointer to UART Tx transfer Buffer */
/ Q1 N2 Y1 A$ n/ |- k - / v7 j; O9 f; `( B; T2 Z! Y6 }
- uint16_t TxXferSize; /*!< UART Tx Transfer size */
, c' C5 D" C: K' H - C! Y. |8 \0 P1 \
- __IO uint16_t TxXferCount; /*!< UART Tx Transfer Counter */
) B* T: x* w+ U, t. R - 9 F( W* i" t f
- uint8_t *pRxBuffPtr; /*!< Pointer to UART Rx transfer Buffer */
: Z% R: X7 L ?/ K4 f
9 P* R1 I+ j7 I" s; e% \9 j7 o- uint16_t RxXferSize; /*!< UART Rx Transfer size */; e! ]' i" ~ s8 ~# e6 s: x3 ^
* u6 B. Q# T# G( e- __IO uint16_t RxXferCount; /*!< UART Rx Transfer Counter */
* c4 g- y7 b% K4 z8 ? - 5 z8 O0 E0 x5 n9 b' o1 |) d& ^: ~
- uint16_t Mask; /*!< UART Rx RDR register mask */
0 }0 l, \* v$ w1 Q! Y8 ]( { - - d# P d- |' i0 U y
- DMA_HandleTypeDef *hdmatx; /*!< UART Tx DMA Handle parameters */9 t' V0 `& X9 y% j2 x- b1 x
- 7 M4 ]! p4 A( `8 z. M/ ~& L
- DMA_HandleTypeDef *hdmarx; /*!< UART Rx DMA Handle parameters */
W) w4 `- w. U* ~% q2 j2 i( d
: q4 ~$ f. @- E' Z/ P1 K5 }% v# N- HAL_LockTypeDef Lock; /*!< Locking object */
5 G5 e6 F- q9 n - ) B8 u4 ~4 ?3 l
- __IO HAL_UART_StateTypeDef gState; /*!< UART state information related to global Handle management, {1 {% i4 k# E. Z8 |9 L3 Q: M
- and also related to Tx operations.
8 O! U+ |2 d7 B a. b1 p& W, { - This parameter can be a value of @ref HAL_UART_StateTypeDef */: r4 |% G6 M! ?3 u
- 0 R0 o% ?) w7 K+ D! T
- __IO HAL_UART_StateTypeDef RxState; /*!< UART state information related to Rx operations.
% Q# |, R' n* T9 s& u+ @& k - This parameter can be a value of @ref HAL_UART_StateTypeDef */4 d1 O+ \1 w0 \2 K( n5 u
$ \ `5 F- a0 n# Y6 l8 L3 m. P- __IO uint32_t ErrorCode; /*!< UART Error code */3 t) n5 E* e+ P; Z( y4 c
) ], P5 N" {' @- }UART_HandleTypeDef;5 b" ~% B, [2 Z8 v. ~# P
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0 e2 Y( L; m- P* d& d m# I因为串口本身是全双工,一个比较合理的设计方法就是再设计一把锁进行保护,而网上的大部分解决方案是注释掉调用锁这个过程,个人是不想改动HAL库的,于是自己写发送函数和接收函数。) l) q7 b9 Y" i& S
9 ^) ?# D* V7 I: v
9 q! v t6 T0 [! M# z! J' N5 o
首先是串口初始化,没有使用HAL_UART_Receive_IT设置接收buffer,而是直接使能接收中断。8 m7 B0 _8 s' \$ Y
- void MX_UART7_Init(void)4 k4 X3 F: @- v5 `, e. Q
- {4 {: g! R1 Q: i
- ; F% n* {/ P/ z) y% [
- huart7.Instance = UART7;2 |- ]" n( _8 Y4 |: ^
- huart7.Init.BaudRate = 115200;8 o0 Q9 c( Z! t& h- g9 H/ G
- huart7.Init.WordLength = UART_WORDLENGTH_8B;
% c2 {) R1 {2 U& S) o+ ]( D7 b - huart7.Init.StopBits = UART_STOPBITS_1;) O/ N5 b% M6 d' y2 M" ~" o3 F
- huart7.Init.Parity = UART_PARITY_NONE;
7 U8 u% d7 ?6 S& F: z - huart7.Init.Mode = UART_MODE_TX_RX;3 _3 T m3 F6 B% w4 B, ]5 d9 i
- huart7.Init.HwFlowCtl = UART_HWCONTROL_NONE;
; @# w+ i' m; Y. j2 v6 L - huart7.Init.OverSampling = UART_OVERSAMPLING_16;, L8 V% ?1 f+ R& L f
- huart7.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
/ b( @. [7 y# o. D3 I. q+ H6 x5 [ - huart7.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
6 X7 r7 ]/ _2 I* P - if (HAL_UART_Init(&huart7) != HAL_OK)* _" T. ~- | [4 s8 P& G5 ?+ @, v
- {
- a3 b0 A/ t: U. b# N: L5 j - Error_Handler();7 s- N" I: w+ `) p- U
- }
9 x- b5 _# N, c2 g& U2 g3 L - __HAL_UART_ENABLE_IT(&huart7, UART_IT_RXNE); //使能接收中断* o: M3 q c2 Z/ o& J
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; o( ~% `5 t* ~1 q0 f3 W4 R中断服务函数这里,因为我只使能了接收中断,所以只对接收中断进行处理,其他中断源直接清除。
$ l A7 ~7 |9 E/ g- void UART7_IRQHandler(void)1 G# ]0 f* L0 J: X+ ?2 {2 u
- {
9 r/ L$ H3 x7 { - char ch;
, z- m8 o2 D) D: `* G - if ((__HAL_UART_GET_FLAG(&huart7, UART_FLAG_RXNE) != RESET) && @& u) `% G& M! z9 g9 K' j* S
- (__HAL_UART_GET_IT_SOURCE(&huart7, UART_IT_RXNE) != RESET))8 V& q: b1 q1 i" p
- {
3 r% d' f$ V; H8 `. i4 k - ch = huart7.Instance->RDR;. }% W1 q. S4 O# i$ U' o
- __HAL_TIM_SET_COUNTER(&htim6, 0);
5 g4 T8 o# `" ]1 Q - if (USART7_RX_STA & 0x8000) return; //上次接收完成的未处理,直接退出
( c, Z$ p* a! t2 n x - if (USART7_RX_STA == 0) //长度为0,接收到的是第一个字节,启动定时器
7 b5 p. ~- l8 D2 C - {: z! Q8 j3 Q5 h6 |4 _* }
- __HAL_TIM_CLEAR_FLAG(&htim6, TIM_FLAG_UPDATE);
* f! e$ O; D$ D - HAL_TIM_Base_Start_IT(&htim6);
3 X0 b- p8 T7 J( r0 e8 |5 E* Q - }2 |$ b! w( G8 N# K& h
- USART7_RX_BUF[USART7_RX_STA & 0x3FFF] = ch;
1 e1 z5 B/ s% n8 t# W- H - USART7_RX_STA++;& k5 Q; a c5 C; q6 f% [
- if (USART7_RX_STA > (USART_REC_LEN - 1))USART7_RX_STA = 0;
/ N/ {$ V! J* B* `4 X - }
" ~ Y k0 R/ L. U% ~' { - else+ Y+ a7 m4 d R9 S1 R
- {- i1 T- Q, M' `, V
- if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_ORE) != RESET)( q; V* F7 ^# X, Z- M
- {% }+ H4 V% ?; x$ F! o2 d# [
- __HAL_UART_CLEAR_OREFLAG(&huart7);
0 a/ ^- x8 d( V: R - }4 y) A- S+ S; j/ C9 k: Y8 D
- if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_NE) != RESET)& V$ P& u0 ^2 A
- {
8 l p# m- y" \! o I$ B2 L - __HAL_UART_CLEAR_NEFLAG(&huart7);
' i ?/ G* O c- I* F - }4 ^; Y( X% L2 t6 R6 _
- if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_FE) != RESET)
) E7 Z% J1 c+ b - {
+ S, j N1 ]6 R7 \- r+ @# z5 ^ - __HAL_UART_CLEAR_FEFLAG(&huart7);
6 D) S% T9 J. K' ?, m( j, E* c1 J - }( u- t. g! m* R; k& Z6 k. m& {4 P
- if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_PE) != RESET), Z3 N/ j8 V- ]& i% t: b6 E4 s: W
- {& r7 w% j3 U l t( e2 h# B
- __HAL_UART_CLEAR_PEFLAG(&huart7);; L2 q# d& i4 p! @' U0 M5 t
- }1 S. K3 d) T$ n& z) I* Z" O; F
- if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_CTS) != RESET)
- W3 a: F. U- Y/ H O5 f - {) Z- {/ N1 }1 e% M/ u
- __HAL_UART_CLEAR_IT(&huart7, UART_FLAG_CTS);
. m, t' ?/ e7 T1 s - }
3 k e; E; I$ {; G" K1 ~ - if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_TXE) != RESET)
9 S+ ?6 e& A; c' U. ^1 o9 p- A - {
/ ?, ^5 z/ s1 F3 ?! H7 G - __HAL_UART_CLEAR_IT(&huart7, UART_FLAG_TXE);
: ^! ^7 j$ {$ Y( Y - }
# \0 g# [) \) \" r# N# R - if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_TC) != RESET)
5 b4 @% \. l5 q! g9 y+ T4 d3 ~ - {4 X$ T4 T- p. G/ o( |/ s$ p7 |! ^. J7 _
- __HAL_UART_CLEAR_IT(&huart7, UART_FLAG_TC);; [9 u" Y' q& `* F
- }
j0 M `7 ^, m- m0 E: O2 a, L - if (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_RXNE) != RESET)+ {8 N2 Z' M. n [
- {
* x3 p- i+ f' S( W9 O' x: A - __HAL_UART_CLEAR_IT(&huart7, UART_FLAG_RXNE);) X9 c' W2 O; d% j6 ?( R/ |4 ~( ^
- }
! v- w; q+ d3 X; u - }" c3 R% X1 n V% d( n
- }- ^; G) h: {+ C# h4 _8 l
复制代码 - F6 ~, u' o9 r# r9 q4 |
发送过程就比较简单了,等待发送完成继续发送就行了。
! Z9 K. j$ z: ? Z: |# V% L/ I- void u7_printf(char* s)% H+ ?& L" p/ v# C
- {
| _5 S# D3 M; _& k. X0 E% X - int i=0;3 M6 w7 i; I/ s* h. B
- while(s[i])' R1 }& G) _8 g3 U+ ~
- {
( |' C8 g9 Q* P+ [: ^ - huart7.Instance->TDR = s[i];" q2 f2 i. U" f) \9 w9 F2 H- E" x
- while (__HAL_UART_GET_FLAG(&huart7, UART_FLAG_TC) == RESET);; [0 t% V; D$ j2 G
- i++;
0 l# s8 I$ S# M/ c8 p - }# _+ K* X" C- e5 K7 {1 P, j$ H
- }
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