1、CubeMX IO口的设置 模拟I2C的IO口都设置为开漏输出,因为电路图上有外部上拉。初始化的时候,2个SDA和SCL都得拉高。所以设置如下: . z) t- Y7 Y# S
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2、HAL库中的us延时函数
# P" }8 `+ W* B: V8 [1 U在HAL库中,只有ms的延时函数HAL_Delay,没有us的延时函数,今天用了网上一个延时函数,发现有问题,搞得整个时钟出了问题,郁闷,折腾了一下午。时间浪费了,通讯模块那边因为这个时钟设置也出了点问题,一直返回复位信息,用了怎么多年的芯片还第一次遇到,Enocean 的TCM310模块,主要这个技术支持也不太好找。= =!还是快速找一个us函数,不是那么精确也可以,直接用空语句测试,后面已经经过测试,下面这个函数做的us延时可以正常移植以前的I2C程序。 - /* USER CODE BEGIN 4 */# k% P0 U+ r h' U: Y% ]' P
- void delay_us(uint32_t Delay)6 }' L H- H' j& f( x
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- uint32_t cnt = Delay * 8;
! J! ]$ J$ ]2 }& N/ k5 Q - uint32_t i = 0;
; A% w) m" g# _' b( y7 n# S - for(i = 0; i < cnt; i++)__NOP();
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# Z4 C% B( {2 W" B0 f" s# @ - /* USER CODE END 4 */
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3、移植I2C代码3.1 SHT21温湿度传感器代码移植没什么问题, i2c.c: - #include "i2c.h"% z. B* r9 w3 [9 \. L
5 ^1 i" b! w1 t6 u9 Y5 J- // ------------------------------------------------------------------$ a5 B9 ]- x) M
- void i2c_init(void) {8 ?* c9 y; u j* e* _% l2 B
-
& T$ a, ~& x- m% { - // the SDA and SCL pins are defined as input with pull up enabled
5 ~9 b1 R: w* G- q) { - // pins are initialized as inputs, ext. pull => SDA and SCL = high
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- }
1 i+ ]* c" [1 B7 G - // ------------------------------------------------------------------" h) h* _5 o) ]6 O
- // send start sequence (S)
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- void i2c_start(void) {
5 f; D7 q" w- b- |- U2 H - sda_high();
* J- Q3 \4 G4 W5 g; c+ j& z. O - delay_us(10);
, n4 b' ?9 B1 G5 h# Y8 e( {* t$ ^" H - scl_high();
- y3 W2 W5 J9 e0 W) j$ N' a - delay_us(10);- r( R) J9 C1 i0 W
- sda_low();
8 ~# g. C$ Q6 c8 f- b! Z0 V* F - delay_us(10);# D4 M6 {; \$ p: P! q
- scl_low();
" ` p c4 j/ g6 @ - delay_us(10);7 j) R+ g" [; H, \& X/ P% T% L
- }
, ~+ X0 N& O3 ^/ a2 P* c/ x - // ------------------------------------------------------------------/ D8 D: C% G& r
- // send stop sequence (P)
- H8 E9 S0 r# u$ x% I - void i2c_stop(void) {
/ O9 s. f1 B4 L1 C( i, j h$ B: n5 E - sda_low(); 3 j @; R6 t& c: T9 \) J
- delay_us(10);- ]+ a: s; A/ J% U5 d4 c; S3 o
- scl_low();
9 e5 E. j X3 g - delay_us(10);
2 j9 b) o. ~) W) v* b - scl_high();
% v# ?; |3 I* K& |6 _7 ]5 T - delay_us(10);
" ?, Z- F1 v p$ r - sda_high();1 H; I# ?' ?" k" r: q
- delay_us(10);9 b3 t$ |* |8 ~, P. W6 ]" P+ D
- }
v' C0 S, {5 u' Q3 ]: a8 | - // ------------------------------------------------------------------, S8 ~" X- I# T& I+ K' R3 z( T
- // returns the ACK or NACK
$ P2 }5 I7 g: s* V7 D, K/ O - uint8 i2c_write(uint8 u8Data)
( [% s) t, U% H. q9 @- L - {
9 B7 H1 N3 z7 w - uint8 u8Bit;
! V+ Q8 C) N! O0 E" W. X2 @ - uint8 u8AckBit;0 w% E5 t. j, ^( ^& D6 e5 D
- // write 8 data bits# `( V$ V) H; ]; J7 ~$ B
- u8Bit = 0x80; //msb first
' f: l& R+ W2 {4 i - while(u8Bit) {
5 w4 j, b& N$ x: I1 G b% o4 K - if(u8Data&u8Bit) { % }' n+ _7 p5 ]1 Q
- sda_high();6 n( r4 m& }! u! Y( w* ^6 [
- delay_us(20);
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- //& compare every bit
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- sda_low();
8 o4 A$ e$ N3 X0 [- S6 R; g - delay_us(20);
0 B4 Q1 T R/ c2 ^! j - }
$ |- ?* W# g( d9 x8 p- } - scl_high();
' [" n1 v0 x! y; h- \/ J, @+ W - delay_us(30);
+ h; I W2 F2 ^" e. }% U1 K/ l+ e - u8Bit >>= 1;
$ t6 [; P' |. `) b8 O% t - //next bit
$ S. e8 R) Q) n8 h& G2 I - scl_low();3 f- K% ^+ i) D; C( u2 h+ X
- delay_us(30);
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- // read acknowledge (9th bit)
! r0 d- B2 V: r5 Q- Q4 G# G - sda_high(); $ v6 r0 U% e, z ~' H' Q9 R
- delay_us(10); $ w) \) U6 E9 K2 C' S! c0 l/ v
- scl_high();' G0 U3 G0 c. [1 o+ \# s% Z
- delay_us(10);
7 T$ i( h: R- v - u8AckBit= sda_read(); //#define sda_read() (sda_port & sda_pin)? 1 :0 ack on bus is low -> u8AckBit = 1 sda_port gpio0 sda_pin SCSEDIO0' D4 S7 {5 p1 Y; r
- delay_us(10);
3 Q; T. v5 C& X: X2 K - scl_low(); ( `4 C6 `6 c6 _! B
- delay_us(10);# N* q' Q: I; p, `: b. \: |* L
- return u8AckBit;
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" h3 f {) A+ g* C% o! w' }* I - // ------------------------------------------------------------------+ r2 b8 @ F( ^0 `% C$ u5 }7 L
- // pass the ack/nack + O5 v# i3 y+ F2 @7 Z
- // returns the read data 0 k. g% L! z/ J1 d+ h2 h+ j
- uint8 i2c_read(uint8 u8Ack)
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4 p6 g; S# k+ p - uint8 u8Bit;
% J: i0 p# P, }) m+ c& J1 A - uint8 u8Data;8 X5 c+ V/ Q$ ?$ G8 t6 X
- u8Bit = 0x80; // msb first
) Q" K. k0 G0 m9 B$ d S - u8Data = 0;
/ b! v5 d: k* n* ?0 @, L0 [1 ]3 Q - while(u8Bit){+ O- d) F& x* X$ d$ d3 E2 I
- scl_high();2 _ `/ I% P! n1 g) M
-
, Z6 W( R8 Y5 d' W2 D/ E' p - delay_us(20);
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- u8Bit >>= 1; //next bit% J0 \* }2 x3 s- Y, A4 `; _* s- i6 a
- u8Data <<= 1;
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# o* f. V4 b6 B6 t$ ^, F - u8Data |= sda_read(); //(sda_port & sda_pin)? 1 :0 sda_port gpio0 sda_pin SCSEDIO01 L$ A# n" K& F6 ~& e& D
- delay_us(20);% C# j1 m8 t6 T/ W. w: y& Z
-
( ?% ]9 T2 z+ Y7 d/ {% A - scl_low();
% r2 V/ K0 q, Z' _& @ - delay_us(50);
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- // 9th bit acknowledge
6 Q! D+ e4 a8 b% l - if(u8Ack==I2C_ACK) {! h+ G* B. S1 R2 |
- sda_low();
3 Y: V/ m; Y, N - delay_us(20);) b7 |7 W9 A0 R3 |) |; f
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- //I2C_ACK=0. b% E% g# R" \: u) u9 Z4 |- m% t) z
- else {* U7 R- Q- Y1 i- R) Z
- sda_high();
7 \% y' E! e" t1 x - delay_us(20);
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- scl_high();
% R5 d* n$ Q9 h7 i - delay_us(20);
2 L) N% F# l+ q: y5 H6 M1 V - scl_low();4 b$ q! T$ p5 d2 W) s! _
- delay_us(20);' X4 x3 D7 x/ _; X- }. \* U T5 y
- sda_high();$ _9 r5 Y* D( \7 l0 L
- delay_us(20); 0 ^+ S2 h8 F- i" `
- return u8Data;
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7 ^6 ]7 P- |1 R! l" vi2c.h: - #ifndef _I2C_H_INCLUDED1 U& o8 [+ h: G0 M
- #define _I2C_H_INCLUDED& Q {7 O2 q/ |) q# h2 s3 c( ^
4 ^$ G* B' D$ z a- #include "main.h"7 b4 w0 C4 w+ b
- #include "Datadef.h"
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2 q: Q& s; D& j5 G4 ^2 R - // #define I2C_CLK_HIGH() HAL_GPIO_WritePin(sht_scl_GPIO_Port,sht_scl_Pin,GPIO_PIN_SET);8 |: j& I" }+ T0 N5 A
- // #define I2C_CLK_LOW() HAL_GPIO_WritePin(sht_scl_GPIO_Port,sht_scl_Pin,GPIO_PIN_RESET);
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6 l6 @; C& V0 y- // #define I2C_DATA_HIGH() HAL_GPIO_WritePin(sht_sda_GPIO_Port,sht_sda_Pin,GPIO_PIN_SET); # K& Y' p8 ~! y4 u: D Z% z( x
- // #define I2C_DATA_LOW() HAL_GPIO_WritePin(sht_sda_GPIO_Port,sht_sda_Pin,GPIO_PIN_RESET);
, F; P2 }4 v) d4 k, @ - // #define I2C_DATA_STATE() (HAL_GPIO_ReadPin(sht_sda_GPIO_Port,sht_sda_Pin) == GPIO_PIN_SET);
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- // #define sda_high() I2C_DATA_HIGH() // set signals to HIGH first before selecting IN -> slew rates
3 H2 c6 K# Y$ M& ^8 ~2 T - // #define sda_low() I2C_DATA_LOW() - d: ^' j* @* y; K6 Q1 n) i
- // #define sda_read() I2C_DATA_STATE() //ack on bus is low -> u8AckBit = 1* P" o2 P# a% T+ M
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- // #define scl_high() I2C_CLK_HIGH() // set signals to HIGH first before selecting IN -> slew rates& a7 v/ x( ]5 O6 g/ B. J. r
- // #define scl_low() I2C_CLK_LOW() % @# X& h' m& R% W" p
' q3 z! M9 ~4 f# t* S- #define sda_high() HAL_GPIO_WritePin(sht_sda_GPIO_Port,sht_sda_Pin,GPIO_PIN_SET);
: y; D7 a. U0 }+ E: E5 O3 s - #define sda_low() HAL_GPIO_WritePin(sht_sda_GPIO_Port,sht_sda_Pin,GPIO_PIN_RESET);
3 K- L3 f. M2 `5 f - #define sda_read() (HAL_GPIO_ReadPin(sht_sda_GPIO_Port,sht_sda_Pin) == GPIO_PIN_SET);
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- #define scl_high() HAL_GPIO_WritePin(sht_scl_GPIO_Port,sht_scl_Pin,GPIO_PIN_SET);
3 g/ U6 p: L6 {' ^/ B - #define scl_low() HAL_GPIO_WritePin(sht_scl_GPIO_Port,sht_scl_Pin,GPIO_PIN_RESET);1 c( p0 i! ~6 r' W
-
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- // ------------------------
0 o+ X! u7 O3 q) a - #define DONOTHING() {;}- H- s* d0 p! p# y4 _1 Y
! ^3 }, n7 f4 I& l6 ]- // ------------------------3 {) H% i! m$ X1 B/ S( w% Q# s, C0 ]
- // command's
" a0 k: o3 t1 h4 l - #define I2C_WRITE 0 2 l& A7 p7 a- ]1 H* `! |: `9 D! H
- #define I2C_READ 14 Y, ^8 O; Q: v6 d# g! c) u
- #define I2C_ACK 05 d0 c" j m9 T# Z) X0 l
- #define I2C_NACK 1. X- S* A1 B; [
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- void i2c_init(void);
+ L$ o0 y/ s4 U1 ^ - void i2c_start(void);
, _0 D7 P T; x' u - void i2c_stop(void);! V/ W7 H, p& f3 d1 m6 ]
- uint8 i2c_write(uint8 u8Data);( A2 q1 \1 ^* Q; N, J
- uint8 i2c_read(uint8 u8Ack);
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- #endif
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SHT21部分的驱动就不用怎么修改了,基本上直接拿过来,把ms延时函数替换一下,就直接用,这里就不贴出来 测试结果:
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板载的HTU21D,实际测试下来,一直会比空气问题高一点,这个问题,我倒是有点头疼,虽然做过分割,不铺铜等一些处理,还是不尽如人意。 3 C I6 x. D% v. z* H" A
转载自:矜辰所致 如有侵权请联系删除5 Y! Q( k. L) R, n1 h
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