lt8900驅(qū)動(dòng)及應(yīng)用編程指南for初學(xué)者

1、#define uchar unsigned charuchar dataH,dataL;/定義全局變量用來保存數(shù)據(jù)/*腳位定義*/sbit SPI_CLK = P14;sbit SPI_MISO = P15; sbit SPI_MOSI = P22;sbit SPI_SS = P23;/片選sbit LT_RESET_N = P24;sbit LT_PKT_FLAG = P25;/LT8900 pkt腳uchar RX_data8;/定義數(shù)據(jù)緩沖區(qū)，保存LT8900收到的數(shù)據(jù)/*從8900讀一個(gè)字節(jié)*/uchar SPI_read8bit()uchar i,data;for(i=0;i<

2、;8;i+)data=data<<1;SPI_CLK=1;_NOP(); /空指令,稍微延時(shí)一下_NOP();_NOP();SPI_CLK=0;if(SPI_MISO=1)data=data|0x01;if(SPI_MISO=0)data=data|0x00;return data;/*往8900寫一個(gè)字節(jié)*/void SPI_write8bit(uchar data)uchar i;for(i=0;i<8;i+)data=data<<1;SPI_CLK=1;_NOP();_NOP();_NOP();SPI_MOSI=C;SPI_CLK=0;/*從地址addr讀數(shù)

3、據(jù)，LT8900寄存器是16位的，*hdata用來保存高8位，ldata用來保存低8位*/void LT8900_writeReg(uchar add,uchar hdata,uchar ldata)SPI_SS=0;/拉低LT8900使能腳，使能LT8900_NOP();SPI_write8bit(add&0X7F);/地址最高位0表示寫_NOP();_NOP();SPI_write8bit(hdata);SPI_write8bit(ldata);_NOP();SPI_SS=1;/完畢重新拉高LT8900使能腳void LT8900_readReg(uchar add)SPI_SS=

4、0; /拉低LT8900使能腳，使能LT8900_NOP();SPI_write8bit(add|0x80);/地址最高位1表示讀_NOP();_NOP();dataH=SPI_read8bit();/data high bytedataL=SPI_read8bit();/data low byte_NOP();SPI_SS=1; /完畢重新拉高LT8900使能腳/*以上4個(gè)函數(shù)就是LT8900最底層的4個(gè)函數(shù)，應(yīng)用程序可以直接調(diào)用。*/void delayms(uchar ms)uchar i,j;for(i=0;i<ms;i+)for(j=0;j<100;j+);/*以下是LT

5、8900接收的初始化代碼*/void LT8900_RX_INIT(void)LT_RESET_N=0;/關(guān)閉芯片delayms(10);LT_RESET_N=1;/開啟芯片，寄存器復(fù)位delayms(50);LT8900_writeReg(0, 0x6f, 0xe0);LT8900_writeReg(1, 0x56, 0x81);LT8900_writeReg(2, 0x66, 0x17);LT8900_writeReg(4, 0x9c, 0xc9);LT8900_writeReg(5, 0x66, 0x37);LT8900_writeReg(7, 0x00, 0x4c);LT8900_wr

6、iteReg(8, 0x6C, 0x90);LT8900_writeReg(9, 0x18, 0x40);LT8900_writeReg(10, 0x7F, 0xFD);LT8900_writeReg(11, 0x00, 0x08);LT8900_writeReg(12, 0x00, 0x00);LT8900_writeReg(13, 0x48, 0xBD);LT8900_writeReg(22, 0x00, 0xff);LT8900_writeReg(23, 0x80, 0x05);LT8900_writeReg(24, 0x00, 0x67);LT8900_writeReg(25, 0x1

7、6, 0x59);LT8900_writeReg(26, 0x19, 0xE0);LT8900_writeReg(27, 0x13, 0x00);LT8900_writeReg(28, 0x18, 0x00);LT8900_writeReg(32, 0x48, 0x00);LT8900_writeReg(33, 0x3f, 0xC7);LT8900_writeReg(34, 0x20, 0x00);LT8900_writeReg(35, 0x03, 0x00);LT8900_writeReg(36, 0x05, 0x0A);LT8900_writeReg(39, 0x55, 0xAA);LT8

8、900_writeReg(40, 0x44, 0x01);LT8900_writeReg(41, 0xB0, 0x00);LT8900_writeReg(42, 0xFD, 0xB0);LT8900_writeReg(43, 0x00, 0x0F);LT8900_writeReg(50, 0x00, 0x00);LT8900_writeReg(52, 0x80, 0x80);LT8900_writeReg(7, 0x00, 0X84);delayms(50);/delay 50ms to let LT8900 for operation接收的應(yīng)用程序可以這樣寫：Void main(void)i

9、nt i;LT8900_RX_INIT();While(1)if(LT_PKT_FLAG=1) /如果LT8900的PKT腳被拉高，說明收到了數(shù)據(jù)/* Register 52 的bit813將指示收到多少字節(jié)數(shù)據(jù)，一般來說發(fā)端發(fā)送多少個(gè)字節(jié)的數(shù)據(jù)是確定的，讀這個(gè)字節(jié)用來校驗(yàn)收到的數(shù)據(jù)包數(shù)據(jù)長度是否正確*/LT8900_readReg(52);if(dataH&0x3f) = 8)/這里假定發(fā)端發(fā)的是8個(gè)字節(jié)的數(shù)據(jù)包SPI_SS=0;/使能8900/*向LT8900的Register50發(fā)送讀命令*/SPI_write8bit(50|0x80);_NOP();_NOP();_NOP();

10、_NOP();for(i=0;i<8;i+)RX_datai=SPI_read8bit(); /將8字節(jié)數(shù)據(jù)全部讀出_NOP();_NOP();SPI_SS=1;/*以下兩步是必須的，1.清空FIFO，2.重新設(shè)置頻道，LT8900再次進(jìn)入接收狀態(tài)*/LT8900_writeReg(52, 0x80, 0x80);LT8900_writeReg(7, 0x00, 0X84);/*接下來就可以根據(jù)收到的數(shù)據(jù)(在數(shù)組RX_data中)，去干你想干的事情了*/*以下是LT8900發(fā)送的初始化代碼*/void LT8900_TX_INIT(void)LT_RESET_N=0;/關(guān)閉芯片delay

11、ms(10);LT_RESET_N=1;/開啟芯片，寄存器復(fù)位delayms(50);LT8900_writeReg(0, 0x6f, 0xe0);LT8900_writeReg(1, 0x56, 0x81);LT8900_writeReg(2, 0x66, 0x17);LT8900_writeReg(4, 0x9c, 0xc9);LT8900_writeReg(5, 0x66, 0x37);LT8900_writeReg(7, 0x00, 0x4c);LT8900_writeReg(8, 0x6C, 0x90);LT8900_writeReg(9, 0x18, 0x40);LT8900_wr

12、iteReg(10, 0x7F, 0xFD);LT8900_writeReg(11, 0x00, 0x08);LT8900_writeReg(12, 0x00, 0x00);LT8900_writeReg(13, 0x48, 0xBD);LT8900_writeReg(22, 0x00, 0xff);LT8900_writeReg(23, 0x80, 0x05);LT8900_writeReg(24, 0x00, 0x67);LT8900_writeReg(25, 0x16, 0x59);LT8900_writeReg(26, 0x19, 0xE0);LT8900_writeReg(27, 0

13、x13, 0x00);LT8900_writeReg(28, 0x18, 0x00);LT8900_writeReg(32, 0x48, 0x00);LT8900_writeReg(33, 0x3f, 0xC7);LT8900_writeReg(34, 0x20, 0x00);LT8900_writeReg(35, 0x03, 0x00);LT8900_writeReg(36, 0x05, 0x0A);LT8900_writeReg(39, 0x55, 0xAA);LT8900_writeReg(40, 0x44, 0x01);LT8900_writeReg(41, 0xB0, 0x00);L

14、T8900_writeReg(42, 0xFD, 0xB0);LT8900_writeReg(43, 0x00, 0x0F);LT8900_writeReg(50, 0x00, 0x00);LT8900_writeReg(52, 0x80, 0x80);LT8900_writeReg(7, 0x01, 0x04);delayms(50);/delay 50ms to let LT8900 for operation/*LT8900發(fā)送的一個(gè)應(yīng)用程序*/uchar TX_data8;void main(void)int i;LT8900_TX_INIT();While(1)if(/*這里是你要發(fā)送的條件，條件成立就進(jìn)去發(fā)送*/)/首先把你要發(fā)送的數(shù)據(jù)填充到數(shù)組TX_data，如TX_data0 = 0x07,TX_data1=0x5a,.LT8900_writeReg(7, 0x00, 0X00); /stop tx,停止發(fā)送LT8900_writeReg(52,