Diff: main.cpp

Revision:

0:fa5e89cbad4d

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Oct 15 21:26:18 2012 +0000
@@ -0,0 +1,43 @@
+/*Program Example 7.6: I2C Slave, when called transfers switch state to mbed acting as Master, and displays state of Master's switches on its leds.
+                                                                              */
+
+#include <mbed.h>
+I2CSlave slave(p9, p10);          //Configure I2C slave
+DigitalOut red_led(p25);          //red led
+DigitalOut green_led(p26);        //green led
+DigitalIn  switch_ip1(p5);
+DigitalIn  switch_ip2(p6);
+char switch_word ;                //word we will send
+char recd_val;                    //value received from master
+
+int main()
+{
+    slave.address(0x52);
+    while (1) {
+        //set up switch_word from switches that are pressed
+        switch_word=0xa0; //set up a recognisable output pattern
+        if (switch_ip1==1)
+            switch_word=switch_word|0x01;
+        if (switch_ip2==1)
+            switch_word=switch_word|0x02;
+        slave.write(switch_word); //load up word to send
+        //test for I2C, and act accordingly
+        int i = slave.receive();
+        if (i == 3) {           //slave is addressed, Master will write
+            recd_val= slave.read();
+        }
+        //set leds according to incoming word from slave
+        red_led=0;              //preset both to 0
+        green_led=0;
+        recd_val=recd_val&0x03; //AND out unwanted bits
+        if (recd_val==1)
+            red_led=1;
+        if (recd_val==2)
+            green_led=1;
+        if (recd_val==3) {
+            red_led=1;
+            green_led=1;
+        }
+    }
+}
+