1、概述# @$ |" g: G" m z: V2 B' A
CH455是数码管显示驱动和键盘扫描控制芯片。CH455内置时钟振荡电路,可以动态驱动4位数码管或者32只LED;同时还可以进行28键的键盘扫描;CH455通过SCL和SDA组成的2线串行接口与单片机等交换数据。& Q, a; G! m9 [5 ]1 \9 q
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g7 Z/ ~3 @ Y2 z) [2 f编址 | DIG3 | DIG2 | DIG1 | DIG0 | SEG0 | 07H | 06H | 05H | 04H | SEG1 | 0FH | 0EH | 0DH | 0CH | SEG2 | 17H | 16H | 15H | 14H | SEG3 | 1FH | 1EH | 1DH | 1CH | SEG4 | 27H | 26H | 25H | 24H | SEG5 | 2FH | 2EH | 2DH | 2CH | SEG6 | 37H | 36H | 35H | 34H | SEG0+SEG1 | 3FH | 3EH | 3DH | 3CH |
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注意:INT接单片机的中断接收口,作为按键按下的信号 9 h" b' G, n; ~( G( y' N! Q
: e. b4 u- n$ G# U$ n% C4 A4、程序设计/ d2 i3 ~% {0 v4 Y0 ~6 j: e
这里由于篇幅问题,主要贴一下IIC控制函数:
( k+ Q L0 F, f: s- //--------------------------------------------i2c-------------------------------------------
( W# g1 _: m3 R r - // 设置SDA为输出方向,对于双向I/O需切换为输出& V0 D" q ]8 t* G, G
- void CH455_SDA_D_OUT(): A$ Y, t$ H( m& S! s8 U7 @
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- GPIO_InitTypeDef GPIO_InitStruct = {0};8 L6 n1 O) A8 W. X( W( [2 P; d
- GPIO_InitStruct.Pin = GPIO_PIN_9;
6 ^4 k6 c" N; ]! k - GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
( J c" j6 [' f7 c& g0 R - GPIO_InitStruct.Pull = GPIO_NOPULL;; K& [5 G" K* \6 f5 P- v
- GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
, K! S# e( I: _; j9 E# L - HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
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% S7 m0 `9 p; ^- // 设置SDA为输入方向,对于双向I/O需切换为输入
( R1 p& ~: W/ i - void CH455_SDA_D_IN(). C" m( u9 Z9 ~" Q- L' i
- {
9 m v' [5 o; y, U - GPIO_InitTypeDef GPIO_InitStruct = {0};
9 A8 P: t: O% Q I' m - GPIO_InitStruct.Pin = GPIO_PIN_9;8 O$ p) ^5 ?7 B8 b& e6 k% g
- GPIO_InitStruct.Mode = GPIO_MODE_INPUT;+ U7 s' x- g$ J+ X
- GPIO_InitStruct.Pull = GPIO_NOPULL;
4 E3 g$ d/ J; ?+ K' o3 i' T - HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
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4 V+ b0 j5 L7 ^- w' g" _% _- void CH455_I2c_Start( void ) // 操作起始
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- //DISABLE_KEY_INTERRUPT; //禁止键盘中断,防止开始时被CH455中断而进入中断服务程序中的START4 C5 K9 k& c+ Y9 z, d: N, v
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1 q8 H& H4 K# Q& M; {; o/ L - CH455_SDA_SET; /*发送起始条件的数据信号*/6 |/ U3 J- u5 f% c$ y2 I) F
- CH455_SDA_D_OUT(); /* 设置SDA为输出方向 */
~6 f/ i/ Q& P: W) w+ R% K' L - CH455_SCL_SET;
l4 j1 t/ ?& {9 s# Y: d7 o/ T4 l - CH455_SCL_D_OUT; /* 设置SCL为输出方向 */
& p* @/ p) n+ H# y5 t - HAL_Delay(10);2 y$ v8 G$ |. }4 Z) `* J
- CH455_SDA_CLR; /*发送起始信号*/, e7 G1 C% R4 |" K# b- n0 D7 b% C! |
- HAL_Delay(10); 6 T5 T" [ ]1 `# S' o+ q
- CH455_SCL_CLR; /*钳住I2C总线,准备发送或接收数据 */1 g# ^+ S9 o$ @' L3 E; H
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8 p4 j; [& G- S, j1 n! n- void CH455_I2c_Stop( void ) // 操作结束
3 y4 i+ c* e0 Q3 [ - {
. u& L2 \8 g# h' q4 g6 N - CH455_SDA_CLR;* ]3 q/ D0 x: l# q( L4 c8 e) v! f: ^
- CH455_SDA_D_OUT(); /* 设置SDA为输出方向 */
* |& e0 L! }9 f - HAL_Delay(10);7 }& W1 ]- Q2 G6 U! Z* i
- CH455_SCL_SET;
; U2 D+ t8 \1 y4 \: F7 G3 O - HAL_Delay(10);
+ |, h6 e& g n5 U p6 }$ ~& @ - CH455_SDA_SET; /*发送I2C总线结束信号*/ a1 z: ]! W3 i' a# R
- HAL_Delay(10);
5 E5 Z: X2 i' Z! T7 z. { - CH455_SDA_D_IN(); /* 设置SDA为输入方向 */
p1 p* i+ l( D& M - //ENABLE_KEY_INTERRUPT;
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1 p9 H% ]- E+ q& U" ^- void CH455_I2c_WrByte( uint8_t dat ) //写一个字节数据, d2 ~) V9 C2 G' y, \' ~
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, U! H. S7 N7 R! a6 ] - uint8_t i;, i1 a# N; X$ t/ W0 n9 x; a% ?5 Z1 r
- CH455_SDA_D_OUT(); /* 设置SDA为输出方向 */
; m7 X+ s" P. a8 X; L+ ?" T - for( i = 0; i != 8; i++ ) // 输出8位数据
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- if( dat & 0x80 )
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; m* G( }/ Q. v6 O& K - CH455_SDA_SET;2 {2 p; [$ g/ ^' b! F9 Y3 w
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- CH455_SDA_CLR;) n; R; c- o, t1 I, X, C
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- HAL_Delay(10);
3 n2 v- f$ Z6 p1 H" F/ e# f( N - CH455_SCL_SET;
" C4 u4 |3 V5 } - dat <<= 1;3 c/ j- \" t; H( G g8 f
- HAL_Delay(10); // 可选延时. N' M& _. A* S7 g4 s+ x6 a& F
- CH455_SCL_CLR;
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- K' d1 B( C& o+ o$ p - CH455_SDA_D_IN(); /* 设置SDA为输入方向 */9 Y9 \# y% N2 N8 h# q* I* E
- CH455_SDA_SET;! p6 I9 v9 U# B$ r& m; [+ b3 `
- HAL_Delay(10);
: R6 r* z2 c. W) C7 A - CH455_SCL_SET; // 接收应答" \: G+ t5 j$ y" I* C
- HAL_Delay(10);! V Q# x6 B' D2 |: x8 |0 V
- CH455_SCL_CLR;
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- uint8_t CH455_I2c_RdByte( void ) //读一个字节数据
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- uint8_t dat,i;
0 Y# e$ @ {( `, v+ s3 F ? - CH455_SDA_SET;
* ?) x- P5 C4 K- u* V - CH455_SDA_D_IN(); /* 设置SDA为输入方向 */
9 {# ?! f) c6 I7 D - dat = 0;. w2 u! \$ T0 q4 s0 S
- for( i = 0; i != 8; i++ ) // 输入8位数据0 k# c4 I0 w2 U6 i7 j6 \4 e' x
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- HAL_Delay(10); // 可选延时
( j6 m& K, A" ?5 [) V - CH455_SCL_SET;/ H% Y2 V" r4 p# b$ ?0 b+ x
- HAL_Delay(10); // 可选延时1 ?+ s, G( e% y* b" _8 J
- dat <<= 1;& P* W. [: }. I$ ~& g
- if( CH455_SDA_IN ) dat++; // 输入1位
* r! @( Q6 q0 d4 d& X0 d - CH455_SCL_CLR; n6 S, Q, [# x9 S r/ M
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- CH455_SDA_SET;
" O% F' {( {% V7 M - HAL_Delay(10);
. c2 B( b: K" ]7 y8 G1 t - CH455_SCL_SET; // 发出无效应答
s& p6 R* t4 J. `* Z8 U - HAL_Delay(10);
9 _/ Z5 j6 t7 J9 l5 j7 t& x5 R - CH455_SCL_CLR;
. P- Y$ q! T( q* V" |7 L+ V - return dat;
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- void CH455_Write( uint16_t cmd ) //写命令/ F" u. O$ r& A# _ a
- {
4 v4 z/ L' [ @9 B6 ] - CH455_I2c_Start(); //启动总线
4 T! I1 x- @$ a, E9 Q2 s - CH455_I2c_WrByte(((uint8_t)(cmd>>7)&CH455_I2C_MASK)|CH455_I2C_ADDR); w5 L! a! B6 d
- CH455_I2c_WrByte((uint8_t)cmd); //发送数据
4 A; M4 F0 B$ b& Y1 Q4 a" u" N - CH455_I2c_Stop(); //结束总线 - r$ H. X% A2 ]/ q% |7 M4 K
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- uint8_t CH455_Read( void ) //读取按键
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- uint8_t keycode;/ H3 L7 z5 S' U5 R
- CH455_I2c_Start(); //启动总线8 T! u+ f( f9 Q. i( S3 `
- CH455_I2c_WrByte((uint8_t)(CH455_GET_KEY>>7)&CH455_I2C_MASK|0x01|CH455_I2C_ADDR);
- } Z" \8 L @; N; p - keycode=CH455_I2c_RdByte(); //读取数据; J$ T. d* U* S
- CH455_I2c_Stop(); //结束总线
9 M, o$ i5 h! g! N2 x. @, k1 z3 y - return keycode;( c! X! }6 ?% S6 z; w
- }
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主函数中记得加上开中断和键盘: + n" }' c5 m( a) i" ?1 j
- HAL_ADC_Start_IT(&hadc1);3 | ~# q8 |) P, t, J- P# \7 F
- CH455_Write( CH455_7SEG_ON );// 开启显示和键盘,8段显示方式
复制代码
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