Gerardo CR / Mbed 2 deprecated Inst_SPI-Master

SPI-Master

Dependencies:   mbed

main.cpp@0:795863b0916e, 2014-09-26 (annotated)

Committer:
gerardo_carmona
Date:
Fri Sep 26 00:04:44 2014 +0000
Revision:
0:795863b0916e
SPI-Master

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gerardo_carmona 0:795863b0916e 1 /*Program Example 7.2. Sets the mbed up as Master, and exchanges data with a
gerardo_carmona 0:795863b0916e 2 slave, sending its own switch positions, and displaying those of the slave.
gerardo_carmona 0:795863b0916e 3 */
gerardo_carmona 0:795863b0916e 4
gerardo_carmona 0:795863b0916e 5 #include "mbed.h"
gerardo_carmona 0:795863b0916e 6
gerardo_carmona 0:795863b0916e 7 SPI ser_port(D11, D12, D13); // mosi, miso, sclk
gerardo_carmona 0:795863b0916e 8 DigitalOut red_led(LED_RED); //red led
gerardo_carmona 0:795863b0916e 9 DigitalOut green_led(LED_GREEN); //green led
gerardo_carmona 0:795863b0916e 10 DigitalOut cs(D2); //this acts as “slave select”
gerardo_carmona 0:795863b0916e 11 DigitalIn switch_ip1(SW2);
gerardo_carmona 0:795863b0916e 12 DigitalIn switch_ip2(SW3);
gerardo_carmona 0:795863b0916e 13
gerardo_carmona 0:795863b0916e 14 char switch_word ; //word we will send
gerardo_carmona 0:795863b0916e 15 char recd_val; //value return from slave
gerardo_carmona 0:795863b0916e 16
gerardo_carmona 0:795863b0916e 17 //continued over
gerardo_carmona 0:795863b0916e 18
gerardo_carmona 0:795863b0916e 19 int main() {
gerardo_carmona 0:795863b0916e 20 switch_ip1.mode(PullUp);
gerardo_carmona 0:795863b0916e 21 switch_ip2.mode(PullUp);
gerardo_carmona 0:795863b0916e 22 red_led = 1;
gerardo_carmona 0:795863b0916e 23 green_led=1;
gerardo_carmona 0:795863b0916e 24 while (1){
gerardo_carmona 0:795863b0916e 25 //Default settings for SPI Master chosen, no need for further configuration
gerardo_carmona 0:795863b0916e 26 //Set up the word to be sent, by testing switch inputs
gerardo_carmona 0:795863b0916e 27 switch_word=0xa0; //set up a recognisable output pattern
gerardo_carmona 0:795863b0916e 28 if (switch_ip1==0)
gerardo_carmona 0:795863b0916e 29 switch_word=switch_word|0x01; //OR in lsb
gerardo_carmona 0:795863b0916e 30 if (switch_ip2==0)
gerardo_carmona 0:795863b0916e 31 switch_word=switch_word|0x02; //OR in next lsb
gerardo_carmona 0:795863b0916e 32 cs = 0; //select slave
gerardo_carmona 0:795863b0916e 33 recd_val=ser_port.write(switch_word); //send switch_word and receive data
gerardo_carmona 0:795863b0916e 34 cs = 1;
gerardo_carmona 0:795863b0916e 35 wait(0.01);
gerardo_carmona 0:795863b0916e 36 //set leds according to incoming word from slave
gerardo_carmona 0:795863b0916e 37 red_led=1; //preset both to 0
gerardo_carmona 0:795863b0916e 38 green_led=1;
gerardo_carmona 0:795863b0916e 39 recd_val=recd_val&0x03; //AND out unwanted bits
gerardo_carmona 0:795863b0916e 40
gerardo_carmona 0:795863b0916e 41 if (recd_val==0x1)
gerardo_carmona 0:795863b0916e 42 red_led=0;
gerardo_carmona 0:795863b0916e 43
gerardo_carmona 0:795863b0916e 44 if (recd_val==0x2)
gerardo_carmona 0:795863b0916e 45 green_led=0;
gerardo_carmona 0:795863b0916e 46
gerardo_carmona 0:795863b0916e 47 if (recd_val==0x3){
gerardo_carmona 0:795863b0916e 48 red_led=0;
gerardo_carmona 0:795863b0916e 49 green_led=0;
gerardo_carmona 0:795863b0916e 50 }
gerardo_carmona 0:795863b0916e 51
gerardo_carmona 0:795863b0916e 52 }
gerardo_carmona 0:795863b0916e 53 }