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9 years ago.
RTOS and Serial
Hello everybody First sorry for my poor English. I'm quite new to mbed and for a school project I want to use the RTOS possibility from mbed. My project is to control a robot, a modified m3pi, with a second mbed en Xbee. I managed to use picojson library to handle the communication. The next step is to use RTOS so I can control the robot and send data back to the second mbed. I wrote a simple test program to learn more about the RTOS library. My problem is reading the data. Sending works fine.
#include "mbed.h"
#include "C12832.h"
#include "MMA7660.h"
#include "LM75B.h"
//#include "mbed_rpc.h"
#include "picojson.h"
#include "rtos.h"
Serial xbee (p9, p10);
DigitalOut xbee_res (p30);
C12832 lcd (p5, p7, p6, p8, p11);
Serial pc (USBTX, USBRX);
DigitalOut myled1(LED1);
DigitalOut myled2(LED2);
DigitalOut myled3(LED3);
DigitalOut myled4(LED4);
const int SIZE = 255;
string str, rvalue, rmode, raction, svalue, smode, saction, strvalue, strmode, straction;
char send[SIZE];
char data[SIZE];
char testing [SIZE +1];
char value[10],mode[10], action[10];
char test;
void parse() {
picojson::value ledcontrol;
const char *json = data;
string err = picojson::parse(ledcontrol, json, json + strlen(json));
//pc.printf("res error? %s\r\n", err.c_str());
pc.printf("LED =%s\r\n" , ledcontrol.get("LED").get<string>().c_str());
pc.printf("Mode =%s\r\n" , ledcontrol.get("Mode").get<string>().c_str());
pc.printf("Action =%s\r\n" , ledcontrol.get("Action").get<string>().c_str());
rvalue = ledcontrol.get("Led").get<string>().c_str();
rmode = ledcontrol.get("Mode").get<string>().c_str();
raction = ledcontrol.get("Action").get<string>().c_str();
pc.printf("LED: %s\r\n", rvalue);
}
void serialize(char *value, char *mode, char *action) {
picojson::object ledcontrol;
//picojson::object inner;
ledcontrol["LED"] = picojson::value(svalue);
ledcontrol["Mode"] = picojson::value(smode);
ledcontrol["Action"] = picojson::value(saction);
str = picojson::value(ledcontrol).serialize();
pc.printf("serialized content = %s\r\n" , str.c_str());
}
void writeXbee_thread(void const *args)
{
//while(1)
//{
while (xbee.writeable())
{
pc.printf("%s %s %s\r\n", value, mode, action);
myled4 = !myled4;
pc.printf("Xbee writeable");
pc.printf(send);
xbee.printf("%s\r\n",str.c_str());
pc.printf("Starting PicoJSONSample "__TIME__"\r\n");
pc.printf(">>> serializing \r\n");
serialize(value, mode, action);
pc.printf("Ending PicoJSONSample " __TIME__ "\r\n");
wait_ms(200);
}
//else
// lcd.printf("Xbee is bussy");
//}
Thread::wait(500);
}
void readXbee_thread(void const *args)
{
//while(1)
//{
test = xbee.getc();
pc.printf("%c\r\n",test);
while(xbee.readable())
{
myled1 = !myled1;
int data_size = xbee.scanf("%s\r\n", data);
xbee.scanf("%s", data);
pc.printf("Data size = %d \r\n",data_size);
pc.printf("%s\r\n",data);
pc.printf(">>> parsing \r\n");
parse();
wait_ms(200);
}
//else
// pc.printf("Xbee is bussy");
//}
Thread::wait(500);
}
void readpc_thread(void const *args)
{
char *check;
pc.printf("%c %i", check, sizeof(check -1));
while(sizeof(check -1) != 4)
{
pc.printf("Choose Led2 or Led3\r\n");
pc.printf("Led2 = led2 and Led3= led3\r\n");
pc.scanf("%4s", value);
pc.printf("Choose to flash or switch it on\r\n");
pc.printf("Flash = flash or On = on\n");
pc.scanf("%4s" , mode);
pc.printf("Choose to activate or stop it\r\n");
pc.printf("Stop = stop and Activate = start\r\n");
pc.scanf("%4s", action);
}
svalue = value;
smode = mode;
saction = action;
Thread::wait(500);
}
void flashing(string rvalue)
{
while(rvalue == "led2")
{
myled2 = 1;
wait_ms(200);
myled2 = 0;
wait_ms(200);
}
while(rvalue == "led3")
{
myled3 = 1;
wait_ms(200);
myled3 = 0;
wait_ms(200);
}
}
void stoping()
{
myled2 = 0;
myled3 = 0;
}
int main()
{
xbee.baud(115200);
xbee_res = 0; //Set reset pin to 0
wait_ms(1);//Wait at least one millisecond
xbee_res = 1;//Set reset pin to 1
wait_ms(1);//Wait another millisecond
/*
pc.printf("Choose Led2 or Led3\r\n");
pc.printf("Led2 = led2 and Led3= led3\r\n");
pc.scanf("%10s", value);
pc.printf("Choose to flash or switch it on\r\n");
pc.printf("Flash = flash or On = on\n");
pc.scanf("%10s" , mode);
pc.printf("Choose to activate or stop it\r\n");
pc.printf("Stop = stop and Activate = start\r\n");
pc.scanf("%10s", action);
svalue = value;
smode = mode;
saction = action;
pc.printf("%s %s %s\r\n", value, mode, action);
*/
//Thread thread(readpc_thread);
//Thread thread1(writeXbee_thread);
Thread thread1(readXbee_thread);
while(1)
{
}
}
1 Answer
9 years ago.
Use
RawSerial xbee (p9, p10); RawSerial pc (USBTX, USBRX);
instead of Serial with RTOS
...kevin
Thanks for the tip, When I use getc() I never receive the full string. I tried the following:
char te;
char in[255];
myled3 = 1;
te = xbee.getc();
myled2 = 1;
do
{
int i = 0;
in[i] = xbee.getc();
i++;
wait_ms(10);
pc.printf("%s\r\n",in);
myled1 = 1;
}
while (te !='}');
I received the following: "Action":"start","LED"":"flash"} or {"Action":"start","LED":"fl or {"Action":"start","LED":"flash"} and so on. with scanf I received: {"Action":"start","LED":"led2","Mode":"flash"} an this is correct (picojson format) Also i noticed in the original program that the receiving mbed stays in xbee.readable(). I was thinking when all was received that readable() = 0. He never leaves the while(xbee.readabel()) loop. I tryed that without the thread. Why is that
posted by 10 Apr 2015Hello everybody. At the moment i could solve my problem with threads. I used the following code
void writeXbee_thread(void const *args)
{
while(1)
{
writeXbee(value, mode, action);
Thread::wait(200);
}
}
void writeXbee(string value, string mode, string action)
{
while (xbee.writeable())
{
pc.printf("%s %s %s\r\n", cvalue, cmode, caction);
pc.printf("Xbee writeable");
pc.printf("%s\r\n",str.c_str());
pc.printf("Starting PicoJSONSample "__TIME__"\r\n");
pc.printf(">>> serializing \r\n");
serialize(value, mode, action);
xbee.printf("%s\r\n",str.c_str());
pc.printf("Ending PicoJSONSample " __TIME__ "\r\n");
wait_ms(1000);
if (!down)
Thread::wait(500);
return;
}
lcd.printf("Xbee is bussy");
}
void readXbee_thread(void const *args)
{
while(1)
{
readXbee();
Thread::wait(1000);
}
}
void readXbee()
{
if(xbee.readable())
{
myled4 = 1;
int data_size = xbee.scanf("%s\r\n", data);
xbee.scanf("%s", data);
pc.printf("Data size = %d \r\n",data_size);
pc.printf("%s\r\n",data);
myled4 = 0;
wait_ms(500);
myled4 = 1;
pc.printf(">>> parsing \r\n");
parse();
myled4 = 0;
wait_ms(10);
}
}
and
int main()
{
pc.baud(9600);
xbee.baud(115200);
xbee_res = 0; //Set reset pin to 0
wait_ms(1);//Wait at least one millisecond
xbee_res = 1;//Set reset pin to 1
wait_ms(1);//Wait another millisecond
Thread write (writeXbee_thread);
Thread read (readXbee_thread);
while(1)
{
myled1 = 1;
wait_ms(100);
myled1 = 0;
Thread::wait(500);
}
}
Forgot to mention with problem reading I meant: sometimes I don't receive anything, or only part of it or i receive one protocol but always the mbed freeze after it.This happens random
posted by Swen Pirker 09 Apr 2015