1、概述
1 y% `5 Q6 ^( h$ k9 z 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。& L0 T5 M- ~# a+ t G& O
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2、键码
& z: s7 ]' ?' ]+ j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 |
! g0 v( U+ O) p) O/ N3、原理图接线 6 W q' U: h0 m% N
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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
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4、程序设计3 R* @5 e( m8 Y7 t* i
这里由于篇幅问题,主要贴一下IIC控制函数:
5 S( @( v6 x& W3 m8 n- //--------------------------------------------i2c-------------------------------------------' a6 S O% S" o# T
- // 设置SDA为输出方向,对于双向I/O需切换为输出
- I/ N$ x) \, ~4 b5 f5 q L - void CH455_SDA_D_OUT(); D9 ^8 O+ e' d- L$ i
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; \8 Q4 w3 c0 Z( o - GPIO_InitTypeDef GPIO_InitStruct = {0};
8 A, u# W* x3 ?4 _5 j _$ o - GPIO_InitStruct.Pin = GPIO_PIN_9;
% M5 Z, C( ^5 o+ u, E+ o( g8 [ - GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
3 j! s2 [% Q9 h - GPIO_InitStruct.Pull = GPIO_NOPULL;0 V: n, i/ k5 r% `8 G4 q
- GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
+ v- Q+ f. I3 u/ q- F7 ` - HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);4 J. h% M. K8 O/ G
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+ K. {3 L4 v3 n% `) r- // 设置SDA为输入方向,对于双向I/O需切换为输入
/ c- Q3 E& H5 z; B1 T - void CH455_SDA_D_IN()
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- GPIO_InitTypeDef GPIO_InitStruct = {0};
* T$ @0 M1 M2 Z( F' M - GPIO_InitStruct.Pin = GPIO_PIN_9;, j4 k. _( ]: o/ y* p2 c \
- GPIO_InitStruct.Mode = GPIO_MODE_INPUT;# Z: g9 I& x* Z) j/ |5 g
- GPIO_InitStruct.Pull = GPIO_NOPULL;
6 f3 Z* R1 Y8 Z% k. i } - HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
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- 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START+ w; ?" Y7 M6 H! F7 K G' ]! Q) Q
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- CH455_SDA_SET; /*发送起始条件的数据信号*/5 r' l; Z* h$ d: R
- CH455_SDA_D_OUT(); /* 设置SDA为输出方向 */3 X1 A# s# \4 G) i- b
- CH455_SCL_SET;& S6 T, Y1 a, x- x/ }& t" \7 Y+ M9 j
- CH455_SCL_D_OUT; /* 设置SCL为输出方向 */
8 b) c2 T- ? Y - HAL_Delay(10);
& d3 ]$ C i \9 _& Y$ D+ U/ N0 `: u - CH455_SDA_CLR; /*发送起始信号*/& q' g* I& k0 Y; u
- HAL_Delay(10); # r+ a: O' o8 J4 c
- CH455_SCL_CLR; /*钳住I2C总线,准备发送或接收数据 */: P+ T0 R; r1 Y. z$ A- C/ H' r
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' [4 t" ?& h7 f5 t. v& u- void CH455_I2c_Stop( void ) // 操作结束# U" u9 z$ d! ^% V: T
- {
2 N' V! }- N0 z) t% }5 ]. ` - CH455_SDA_CLR;
+ }; d t/ a# E7 d$ x - CH455_SDA_D_OUT(); /* 设置SDA为输出方向 */
! t9 T$ b) v# K7 G: K% u; y - HAL_Delay(10);9 k m% Q3 n9 T. ~7 X# u' C" n
- CH455_SCL_SET;
+ q6 u/ k% c4 _/ d) B$ } - HAL_Delay(10);
) L6 `+ _+ u6 N5 L - CH455_SDA_SET; /*发送I2C总线结束信号*/5 Q. t- ~% K1 }& }; `
- HAL_Delay(10);
1 D- X5 Q8 P4 U$ y6 J! I) A3 X& a: I - CH455_SDA_D_IN(); /* 设置SDA为输入方向 */
& K' _) }4 {" z( Q( R. Q/ _/ ^ - //ENABLE_KEY_INTERRUPT;
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- void CH455_I2c_WrByte( uint8_t dat ) //写一个字节数据8 G P; L: g" Q* Y0 G& N$ z8 ~
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- uint8_t i;* g9 X1 o6 S4 C u# m: j6 Y
- CH455_SDA_D_OUT(); /* 设置SDA为输出方向 */' ?; M6 a) q t9 J7 T9 |6 _4 r& k7 y _
- for( i = 0; i != 8; i++ ) // 输出8位数据; X' Y- i; H: x9 T+ K% j/ _
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- if( dat & 0x80 )
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0 _9 y7 s! u) g, Q - CH455_SDA_SET;% Q$ i& c& a! P
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+ N5 t; U& N; C6 O) g, | - else
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- CH455_SDA_CLR;
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, F9 q7 Q+ {" h - HAL_Delay(10);6 g9 k$ k# r! n; Y! @' L
- CH455_SCL_SET;
( X( s/ F0 d+ d: O" V - dat <<= 1;6 m! u& W' G$ J+ E$ l
- HAL_Delay(10); // 可选延时
: F; O$ W' H' w2 ?' o2 B - CH455_SCL_CLR;
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- CH455_SDA_D_IN(); /* 设置SDA为输入方向 */
! D# G% q j# u. q/ C: Y - CH455_SDA_SET;1 s) N, X: i' o3 O
- HAL_Delay(10);
7 `* w* ?7 \6 e$ G% h2 q3 L - CH455_SCL_SET; // 接收应答
" s3 o: e: u T$ n. c' Q5 S3 P8 P# ? - HAL_Delay(10);) n( T4 }2 B" c5 ]& L
- CH455_SCL_CLR;) f* I8 D8 y. ^; k1 k% O5 o9 g
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4 \, n/ J w. ?& m- uint8_t CH455_I2c_RdByte( void ) //读一个字节数据
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# a$ K L" O" L2 r - uint8_t dat,i;
9 ~) @ y0 |% l2 ]4 U/ V - CH455_SDA_SET;
$ L7 ^5 y4 _' Y - CH455_SDA_D_IN(); /* 设置SDA为输入方向 */
; K8 j+ C" \6 h- ]# ^$ Y. [ - dat = 0;. [8 b1 Z# o" }
- for( i = 0; i != 8; i++ ) // 输入8位数据$ A' r" `6 o2 r. T" a
- {
% c4 V, h4 [: ^1 }- l4 @4 A - HAL_Delay(10); // 可选延时' N) i, m' N, A8 o+ V
- CH455_SCL_SET;0 R0 X' I( ~' W$ y* m k
- HAL_Delay(10); // 可选延时# p1 }- R( P, R. h2 V4 k C" i
- dat <<= 1;
: ?5 _/ L; A; o$ } - if( CH455_SDA_IN ) dat++; // 输入1位
) ^: y' n" C; h8 B- M/ C" [ - CH455_SCL_CLR;
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: C3 O0 m+ h$ G* X+ @: u - CH455_SDA_SET;/ } H0 \1 ]! Q9 a, v* H
- HAL_Delay(10);
. R8 V# |+ J! G# E4 U - CH455_SCL_SET; // 发出无效应答8 h7 T0 R0 T( Z
- HAL_Delay(10);& R1 _8 ^5 P' H: F5 N
- CH455_SCL_CLR;4 }. ~; E$ W' U2 }! J. P- R
- return dat;9 ? J. n) g V: z8 u
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- void CH455_Write( uint16_t cmd ) //写命令& w( p! f+ s5 P
- {
4 W3 z; \8 R9 N, F f - CH455_I2c_Start(); //启动总线4 b# P9 d3 ^% B# b' x+ o
- CH455_I2c_WrByte(((uint8_t)(cmd>>7)&CH455_I2C_MASK)|CH455_I2C_ADDR);5 V+ x& }0 P `+ S
- CH455_I2c_WrByte((uint8_t)cmd); //发送数据# x% E. T0 o3 x' @0 o; P+ P
- CH455_I2c_Stop(); //结束总线 ; E& w* r2 g8 \& j, g
- }
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- uint8_t CH455_Read( void ) //读取按键
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- uint8_t keycode;5 c1 G8 R0 C: j
- CH455_I2c_Start(); //启动总线
" W6 v) x: z% h/ r9 K - CH455_I2c_WrByte((uint8_t)(CH455_GET_KEY>>7)&CH455_I2C_MASK|0x01|CH455_I2C_ADDR);
1 X: `5 L( C- ?! ?. C2 l - keycode=CH455_I2c_RdByte(); //读取数据; {, x2 I+ r2 ~- t/ O& H) r
- CH455_I2c_Stop(); //结束总线
' y% h; I/ a: X3 I* ^ - return keycode;
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主函数中记得加上开中断和键盘:
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- HAL_ADC_Start_IT(&hadc1);) c8 G7 W3 n8 e3 b
- 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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