main.cpp

00001 #include "mbed.h"
00002 
00003 Serial pc(USBTX, USBRX); // tx, rx
00004 
00005 
00006 SPI spi(p5, p6, p7); // mosi, miso, sclk
00007 DigitalOut rst_n(p8); // 
00008 DigitalOut cs_n(p9);
00009 
00010 // p5 : pin19 MOSI
00011 // p6 : pin20 MISO
00012 // p7 : pin01 SCLK
00013 // p8 : pin04 RESET_N
00014 
00015 
00016 
00017 
00018 
00019 int read_reg(int addr);
00020 void write_reg(int addr,int data);
00021 
00022 int read_reg(int addr) {
00023         int retval;
00024         cs_n=0;
00025         wait_us(4000);
00026         spi.write(0x21);
00027         wait_us(1000);
00028         spi.write(addr & 0xFF);
00029         wait_us(1000);
00030         retval = spi.write(0);
00031         wait_us(1000);        
00032         retval = spi.write(0);
00033         wait_us(4000);
00034         cs_n=1;
00035         return retval;    
00036 }
00037     
00038 void write_reg(int addr,int data){
00039         cs_n=0;
00040         wait_us(4000);
00041         spi.write(0x20);
00042         wait_us(1000);
00043         spi.write(addr & 0xFF);
00044         wait_us(1000);
00045         spi.write(data);
00046         wait_us(4000);
00047         cs_n=1;
00048 }
00049 
00050 int main() {
00051     int rw,addr,data;
00052     // 8-bit, SPI mode 2
00053     spi.format(8,2);
00054     // 10kHz
00055     spi.frequency(10000);
00056 
00057     pc.printf("Init device\r\n");
00058 
00059     cs_n  = 1;
00060     rst_n = 0;    
00061     wait_ms(10); 
00062     rst_n = 1;    
00063 
00064     while(1) {
00065         rw = -1;
00066         addr = 0;
00067         data = 0;
00068         pc.printf("Write and Read Address Data? rw(write=0,read=1) addr(hex) data(hex): \r\n");    
00069         pc.scanf("%d %x %x",&rw,&addr,&data);
00070         // Write
00071         cs_n=0;
00072         if ( rw == 0 ) {
00073             write_reg(addr,data);
00074             pc.printf("Wrote %02x @ %02x\r\n",data,addr);
00075             pc.printf("Read  %02x @ %02x\r\n",read_reg(addr),addr);
00076         }
00077         else if (rw == 1 ) {
00078             pc.printf("Read  %02x @ %02x\r\n",read_reg(addr),addr);
00079         }
00080         else if (rw == 2) {
00081             for (int i=0; i<10;i++){
00082                 pc.printf("Read data %02x @ %02x\r\n",read_reg(i),i);
00083             }
00084         }
00085         else {
00086             pc.printf("Unknown command\r\n");
00087         }
00088     }
00089 }