Kevin Anderson / Mbed 2 deprecated DataCommFreedom

Using FRDM Board to output data and a clock for communications example.

Dependencies:   mbed

main.cpp@1:4c0c28cc2b2c, 2015-02-26 (annotated)

Committer:
askksa12543
Date:
Thu Feb 26 15:53:11 2015 +0000
Revision:
1:4c0c28cc2b2c
Parent:
0:7c7f4b30d64f
Child:
2:11f32d8cfa11
lab

Who changed what in which revision?

UserRevisionLine numberNew contents of line
askksa12543 0:7c7f4b30d64f 1 #include "mbed.h"
askksa12543 0:7c7f4b30d64f 2 #include "stdio.h"
askksa12543 0:7c7f4b30d64f 3
askksa12543 0:7c7f4b30d64f 4 DigitalOut myled(LED1); // Led on board
askksa12543 0:7c7f4b30d64f 5 DigitalOut clock_pin(D8); //send clock pulse
askksa12543 0:7c7f4b30d64f 6 DigitalOut serial_out(D7); //serial tx
askksa12543 0:7c7f4b30d64f 7 Timer t; //timer for controlling the clock and data skew
askksa12543 0:7c7f4b30d64f 8 int msecs; //clock time needed for data transfer
askksa12543 0:7c7f4b30d64f 9 int sksecs; //skew time
askksa12543 0:7c7f4b30d64f 10 int skew_flag; //skew flag for while loop
askksa12543 0:7c7f4b30d64f 11
askksa12543 0:7c7f4b30d64f 12 int main() {
askksa12543 0:7c7f4b30d64f 13
askksa12543 0:7c7f4b30d64f 14 //turn on red led to show programming has worked
askksa12543 0:7c7f4b30d64f 15 myled = 0;
askksa12543 0:7c7f4b30d64f 16 //initialize output pins
askksa12543 0:7c7f4b30d64f 17 clock_pin = 0;
askksa12543 0:7c7f4b30d64f 18 serial_out = 0;
askksa12543 0:7c7f4b30d64f 19 //skew flag
askksa12543 0:7c7f4b30d64f 20 skew_flag = 1;
askksa12543 0:7c7f4b30d64f 21
askksa12543 0:7c7f4b30d64f 22 //set timers
askksa12543 1:4c0c28cc2b2c 23 msecs = 2000;
askksa12543 1:4c0c28cc2b2c 24 sksecs = 1800;
askksa12543 0:7c7f4b30d64f 25
askksa12543 0:7c7f4b30d64f 26 //output a clock pulse and data.
askksa12543 0:7c7f4b30d64f 27 while(1)
askksa12543 0:7c7f4b30d64f 28 {
askksa12543 0:7c7f4b30d64f 29 //start timer for clock
askksa12543 0:7c7f4b30d64f 30 t.start();
askksa12543 0:7c7f4b30d64f 31 //wait until the timer has reached the set time.
askksa12543 0:7c7f4b30d64f 32 while(t.read_ms() < msecs)
askksa12543 0:7c7f4b30d64f 33 {
askksa12543 0:7c7f4b30d64f 34 //switch data just before clock goes high
askksa12543 0:7c7f4b30d64f 35 if(!clock_pin && skew_flag && t.read_ms() > sksecs)
askksa12543 0:7c7f4b30d64f 36 {
askksa12543 0:7c7f4b30d64f 37 //switch data signal
askksa12543 0:7c7f4b30d64f 38 serial_out = !serial_out;
askksa12543 0:7c7f4b30d64f 39 skew_flag = 0;
askksa12543 0:7c7f4b30d64f 40 }
askksa12543 0:7c7f4b30d64f 41 }
askksa12543 0:7c7f4b30d64f 42 //stop and reset the timer
askksa12543 0:7c7f4b30d64f 43 t.stop();
askksa12543 0:7c7f4b30d64f 44 t.reset();
askksa12543 0:7c7f4b30d64f 45 //switch clock signal
askksa12543 0:7c7f4b30d64f 46 clock_pin = !clock_pin;
askksa12543 0:7c7f4b30d64f 47 //reset skew flag
askksa12543 0:7c7f4b30d64f 48 skew_flag = 1;
askksa12543 0:7c7f4b30d64f 49 }
askksa12543 1:4c0c28cc2b2c 50 }
askksa12543 1:4c0c28cc2b2c 51
askksa12543 1:4c0c28cc2b2c 52 //crc = x^5+x^4+x^2+1