I was trying to write items to the EEPROM and later read them out. I was finding the reading back I was not getting the same as I put in at times. I narrow down to an example I can show you. Below I read into variables 2 address.
const int start_add_type = (EEPROM.length() - 10);
const int start_add_id = (EEPROM.length() - 4);
I then look at the value (via RS232)
Serial.begin(9600);
Serial.println(start_add_type);
Serial.println(start_add_id);
of them at the start of the setup() and see I get
1014
1020
I then look again at the end
Serial.println(start_add_type);
Serial.println(start_add_id);
and I get
1014
818
I cannot see why this should change. I did try calling them const e.g. const
const int start_add_type = (EEPROM.length() - 10);
const int start_add_id = (EEPROM.length() - 4);
but this gave the same result. So here I sit very puzzled at what I must have missed. Anyone got any idea?
#include "EEPROM.h"
int start_add_type = (EEPROM.length() - 10);
int start_add_id = (EEPROM.length() - 4);
char ID[7] = "ENCPG2";
char Stored_ID[5];
char Input[10];
//String Type;
void setup()
{
Serial.begin(9600);
Serial.println(start_add_type);
Serial.println(start_add_id);
// start_add = (EEPROM.length() - 10); // use this method to be PCB independent.
for (int i = 0; i < 6; i++)
{
Stored_ID[i] = EEPROM.read(start_add_type + i); // Read the ID into the EEPROM.
}
if (Stored_ID != ID) // Check if the one we have got is the same as the one in this code ID[7]
{
for (int i = 0; i < 6; i++)
{
EEPROM.write(start_add_type + i, ID[i]); // Write the ID into the EEPROM.
}
}
Serial.println(start_add_type);
Serial.println(start_add_id);
}
void loop()
{
}
You are overwriting your memory in this loop:
for (int i = 0; i < 6; i++)
{
Stored_ID[i] = EEPROM.read(start_add_type + i);
}
Stored_ID array is 5 bytes long, so writing to Stored_ID[5] will rewrite also the start_add_id variable, thus the weird value 818, which equals to 0x0332 HEX and 0x32 is the '2' character of your ID
For fixing this issue, declare Stored_ID in this way:
char Stored_ID[6];
if (Stored_ID != ID)
This is nonsense: You compare two different addresses, which are never equal. If you want to compare the content, you should do it in a loop. (e.g. directly when reading the EEPROM value into Stored_ID[i] )
Alternatively, Stored_ID could be a 0-terminated text as well and you might use
if (strcmp(Stored_ID, ID) != 0)
Related
My code looks something like this:
#define SIZE_OF_ARRAY 1000
const long myArray[SIZE_OF_ARRAY] PROGMEM = {
1610514120L,
1613070480L,
1615630980L,
1618194720L,
1620759660L,
1623322440L,
1625879820L,
1628430600L,
1630975920L,
1633518300L,
1636060500L,
1638603840L,
1641148500L,
1643694540L,
... // All the way to 1000 elements
}
void setup() {
Serial.begin(115200);
for( int i = 0; i < SIZE_OF_ARRAY; i++){
long currentNumber = myArray[i];
// These also do not work:
//long currentNumber = pgm_read_word_near(myArray + i);
//long currentNumber = pgm_read_dword_near(myArray + i);
Serial.println(currentNumber);
}
}
But when I run this code, I get completely random junk data:
0
65536
0
-1195853640
8843185
-566231498
-310626819
-854754529
263210495
-325068311
-159567983
-1770239
-29784074
1054840810
-293611553
-436273185
-566231498
-310626819
-854754529
263210495
... all the way up to 1000
How can I access that array to get the data I put in it? I am not very familiar with C and the difference between variables and pointers, but it works without the PROGMEM flag so I assumed it would work with it as well.
Looks like the answer was to use:
void setup() {
Serial.begin(115200);
for( int i = 0; i < SIZE_OF_ARRAY; i++){
unsigned long currentNumber = pgm_read_dword_near(myArray + i);
Serial.println(currentNumber);
}
}
And to redefine the long array as:
const unsigned long myArray[SIZE_OF_ARRAY] PROGMEM = {
1610514120UL,
1613070480UL,
1615630980UL,
1618194720UL,
1620759660UL,
...
}
Because I was also running into long overflow errors
I'm trying to use a teensy 4.1 as an interface between an encoder and ROS thanks to micro-ros (arduino version).
I would like to publish position of a wheel to the /jointState topic with the teensy but there is no example on the micro-ros arduino Github repo.
I've tried to inspect the sensormsgs/msg/jointState message struct but everything is a bit fuzzy and I don't understand how to make it works. I can't understand what is rosidl_runtime_c__double__Sequence type.
I've tried several things but I always get an error about operand types
no match for 'operator=' (operand types are 'rosidl_runtime_c__String' and 'const char [18]')
msg.name.data[0] = "drivewhl_1g_joint";
Here is my arduino code
#include <micro_ros_arduino.h>
#include <stdio.h>
#include <rcl/rcl.h>
#include <rcl/error_handling.h>
#include <rclc/rclc.h>
#include <rclc/executor.h>
#include <sensor_msgs/msg/joint_state.h>
rcl_publisher_t publisher;
sensor_msgs__msg__JointState msg;
rclc_executor_t executor;
rclc_support_t support;
rcl_allocator_t allocator;
rcl_node_t node;
rcl_timer_t timer;
#define LED_PIN 13
#define RCCHECK(fn) { rcl_ret_t temp_rc = fn; if((temp_rc != RCL_RET_OK)){error_loop();}}
#define RCSOFTCHECK(fn) { rcl_ret_t temp_rc = fn; if((temp_rc != RCL_RET_OK)){}}
void error_loop(){
while(1){
digitalWrite(LED_PIN, !digitalRead(LED_PIN));
delay(100);
}
}
void timer_callback(rcl_timer_t * timer, int64_t last_call_time)
{
RCLC_UNUSED(last_call_time);
if (timer != NULL) {
RCSOFTCHECK(rcl_publish(&publisher, &msg, NULL));
//
//Do not work
//msg.name=["drivewhl_1g_joint","drivewhl_1d_joint","drivewhl_2g_joint","drivewhl_2d_joint"];
//msg.position=["1.3","0.2", "0","0"];
msg.name.size = 1;
msg.name.data[0] = "drivewhl_1g_joint";
msg.position.size = 1;
msg.position.data[0] = 1.85;
}
}
void setup() {
set_microros_transports();
pinMode(LED_PIN, OUTPUT);
digitalWrite(LED_PIN, HIGH);
delay(2000);
allocator = rcl_get_default_allocator();
//create init_options
RCCHECK(rclc_support_init(&support, 0, NULL, &allocator));
// create node
RCCHECK(rclc_node_init_default(&node, "micro_ros_arduino_node", "", &support));
// create publisher
RCCHECK(rclc_publisher_init_default(
&publisher,
&node,
ROSIDL_GET_MSG_TYPE_SUPPORT(sensor_msgs, msg, JointState),
"JointState"));
// create timer,
const unsigned int timer_timeout = 1000;
RCCHECK(rclc_timer_init_default(
&timer,
&support,
RCL_MS_TO_NS(timer_timeout),
timer_callback));
// create executor
RCCHECK(rclc_executor_init(&executor, &support.context, 1, &allocator));
RCCHECK(rclc_executor_add_timer(&executor, &timer));
}
void loop() {
delay(100);
RCSOFTCHECK(rclc_executor_spin_some(&executor, RCL_MS_TO_NS(100)));
}
I'm a beginner with Ros and C, it may be a very dumb question but I don't know how to solve it. Thanks for your help !
rosidl_runtime_c__String__Sequence is a structure used to old string data that is to be transmitted. Specifically it is a sequence of rosidl_runtime_c__String data. You're running into an error because rosidl_runtime_c__String is also a struct itself with no custom operators defined. Thus, your assignment fails since the types are not directly convertible. What you need to do instead is use the rosidl_runtime_c__String.data field. You can see slightly more info here
void timer_callback(rcl_timer_t * timer, int64_t last_call_time)
{
RCLC_UNUSED(last_call_time);
if (timer != NULL) {
//msg.name=["drivewhl_1g_joint","drivewhl_1d_joint","drivewhl_2g_joint","drivewhl_2d_joint"];
//msg.position=["1.3","0.2", "0","0"];
msg.name.size = 1;
msg.name.data[0].data = "drivewhl_1g_joint";
msg.name.data[0].size = 17; //Size in bytes excluding null terminator
msg.position.size = 1;
msg.position.data[0] = 1.85;
RCSOFTCHECK(rcl_publish(&publisher, &msg, NULL));
}
}
I also spent quite some time trying to get publishing JointState message from my esp32 running microros, and also couldn't find working example. Finally, i was successful, maybe it will help someone.
In simple words:
.capacity contains max number of elements
.size contains actual number of elements (strlen in case of string)
.data should be allocated as using malloc as .capacity * sizeof()
each string within sequence should be allocated separately
This is my code that allocates memory for 12 joints, named j0-j11. Good luck!
...
// Declarations
rcl_publisher_t pub_joint;
sensor_msgs__msg__JointState joint_state_msg;
...
// Create publisher
RCCHECK(rclc_publisher_init_default(&pub_joint, &node,
ROSIDL_GET_MSG_TYPE_SUPPORT(sensor_msgs, msg, JointState),
"/hexapod/joint_state"));
//Allocate memory
joint_state_msg.name.capacity = 12;
joint_state_msg.name.size = 12;
joint_state_msg.name.data = (std_msgs__msg__String*) malloc(joint_state_msg.name.capacity*sizeof(std_msgs__msg__String));
for(int i=0;i<12;i++) {
joint_state_msg.name.data[i].data = malloc(5);
joint_state_msg.name.data[i].capacity = 5;
sprintf(joint_state_msg.name.data[i].data,"j%d",i);
joint_state_msg.name.data[i].size = strlen(joint_state_msg.name.data[i].data);
}
joint_state_msg.position.size=12;
joint_state_msg.position.capacity=12;
joint_state_msg.position.data = malloc(joint_state_msg.position.capacity*sizeof(double));
joint_state_msg.velocity.size=12;
joint_state_msg.velocity.capacity=12;
joint_state_msg.velocity.data = malloc(joint_state_msg.velocity.capacity*sizeof(double));
joint_state_msg.effort.size=12;
joint_state_msg.effort.capacity=12;
joint_state_msg.effort.data = malloc(joint_state_msg.effort.capacity*sizeof(double));
for(int i=0;i<12;i++) {
joint_state_msg.position.data[i]=0.0;
joint_state_msg.velocity.data[i]=0.0;
joint_state_msg.effort.data[i]=0.0;
}
....
//Publish
RCSOFTCHECK(rcl_publish(&pub_joint, &joint_state_msg, NULL));
I have made a program for my Arduino which will sort an array of fifty random numbers in ascending or descending order, I think I have got it all right, but when I run it I get an error message "expected unqualified-id before 'for' ".
int array [50];
int i = 0;
void setup() {
Serial.begin(9600); // Load Serial Port
}
void loop() {
// put your main code here, to run repeatedly:
Serial.println ("Position " + array[i]);
delay (2000);
}
for (i <= 50) { <-----*Here is where the error highlights*--->
int n = random (251); // Random number from 0 to 250
array[i] = n;
i++;
}
// Bubble sort function
void sort (int a[], int size) {
for(int i=0; i<(size-1); i++) {
for(int o=0; o<(size-(i+1)); o++) {
if(a[o] > a[o+1]) {
int t = a[o];
a[o] = a[o+1];
a[o+1] = t;
}
}
}
}
I have annotated where the error is shown. I need to get past this to test my code, I have no clue on how to fix it!
You have written it wrong. There is pseudocode of for loop:
for(datatype variableName = initialValue; condition; operation){
//your in loop code
}
//Code wich will be executed after end of for loop above
In your case it will look like this:
for(int i = 0; i < 50 ; i++){
int n = random (251); // Random number from 0 to 250
array[i] = n;
}
Another thing is, that you are trying to iterate the array. The first index is 0. It means the last index is 49 not 50. If you try to access 50th index it will crash your program.
Last thing is, that the for loop we are talking about is out of any method. It will never be executed.
The for loop requires three parts to its parameters:
A variable to count iterations
A condition that must be true to continure
A increment factor
Each part should be separated by a semicolon
So your for loop should start out like this:
for(int i = 0;i <= 50; i++){
//code here
}
Official arduino For Loop Reference
My chip just stop doing anything. sometimes it prints good results, sometimes its not, i just cant understand whats wrong with this code( and generally any time you using Strings it happens )
void ParseGetRequest(char* data)
{
String parseGET=data;
String from="GET /";
String to="HTTP";
int ind1 = parseGET.indexOf(from);
int ind2 = parseGET.indexOf(to);
parseGET=parseGET.substring(ind1+from.length(), ind2-1);
strcpy(data, parseGET.c_str () );
}
And calling it with :
void readWifDataAsSever(char* reqData)
{
uint8_t buffer[128] = {0};
uint8_t mux_id;
uint32_t len = wifi.recv(&mux_id, buffer, sizeof(buffer), 100);
char serverData[100]={0};
if (len > 0)
{
for(uint32_t i = 0; i < len; i++)
serverData[i]=(char)buffer[i];
ParseGetRequest( serverData ); ///****** the call
Serial.println(serverData); // prints only part of the values
//here the chip just freeze and stop the main loop
NULL termination !!!!
serverData[len ] = '\0';
I am working with an Arduino and Processing with the Arduino library.
I get the error "The function bitWrite(byte, int, int) does not exist.";
it seams that processing + Arduino bitWrite function are not working together.
its raised due to this line:
arduino.bitWrite(data,desiredPin,desiredState);
my goal in this project is modifying a music reactive sketch to work with shift registers.
Here is my full code:
Arduino_Shift_display
import ddf.minim.*;
import ddf.minim.analysis.*;
import processing.serial.*;
import cc.arduino.*;
int displayNum = 8;
Arduino arduino;
//Set these in the order of frequency - 0th pin is the lowest frequency,
//while the final pin is the highest frequency
int[] lastFired = new int[displayNum];
int datapin = 2;
int clockpin = 3;
int latchpin = 4;
int switchpin = 7;
byte data = 0;
//Change these to mess with the flashing rates
//Sensitivity is the shortest possible interval between beats
//minTimeOn is the minimum time an LED can be on
int sensitivity = 75;
int minTimeOn = 50;
String mode;
String source;
Minim minim;
AudioInput in;
AudioPlayer song;
BeatDetect beat;
//Used to stop flashing if the only signal on the line is random noise
boolean hasInput = false;
float tol = 0.005;
void setup(){
// shift register setup
arduino.pinMode(datapin, arduino.OUTPUT);
arduino.pinMode(clockpin, arduino.OUTPUT);
arduino.pinMode(latchpin, arduino.OUTPUT);
arduino.digitalWrite(switchpin, arduino.HIGH);
//Uncomment the mode/source pair for the desired input
//Shoutcast radio stream
//mode = "radio";
//source = "http://scfire-ntc-aa05.stream.aol.com:80/stream/1018";
//mode = "file";
//source = "/path/to/mp3";
mode = "mic";
source = "";
size(512, 200, P2D);
minim = new Minim(this);
arduino = new Arduino(this, Arduino.list()[1]);
minim = new Minim(this);
if (mode == "file" || mode == "radio"){
song = minim.loadFile(source, 2048);
song.play();
beat = new BeatDetect(song.bufferSize(), song.sampleRate());
beat.setSensitivity(sensitivity);
} else if (mode == "mic"){
in = minim.getLineIn(Minim.STEREO, 2048);
beat = new BeatDetect(in.bufferSize(), in.sampleRate());
beat.setSensitivity(sensitivity);
}
}
void shiftWrite(int desiredPin, int desiredState)
// This function lets you make the shift register outputs
// HIGH or LOW in exactly the same way that you use digitalWrite().
// Like digitalWrite(), this function takes two parameters:
// "desiredPin" is the shift register output pin
// you want to affect (0-7)
// "desiredState" is whether you want that output
// to be HIGH or LOW
// Inside the Arduino, numbers are stored as arrays of "bits",
// each of which is a single 1 or 0 value. Because a "byte" type
// is also eight bits, we'll use a byte (which we named "data"
// at the top of this sketch) to send data to the shift register.
// If a bit in the byte is "1", the output will be HIGH. If the bit
// is "0", the output will be LOW.
// To turn the individual bits in "data" on and off, we'll use
// a new Arduino commands called bitWrite(), which can make
// individual bits in a number 1 or 0.
{
// First we'll alter the global variable "data", changing the
// desired bit to 1 or 0:
arduino.bitWrite(data,desiredPin,desiredState);
// Now we'll actually send that data to the shift register.
// The shiftOut() function does all the hard work of
// manipulating the data and clock pins to move the data
// into the shift register:
arduino.shiftOut(datapin, clockpin, MSBFIRST, data);
// Once the data is in the shift register, we still need to
// make it appear at the outputs. We'll toggle the state of
// the latchPin, which will signal the shift register to "latch"
// the data to the outputs. (Latch activates on the high-to
// -low transition).
arduino.digitalWrite(latchpin, arduino.HIGH);
arduino.digitalWrite(latchpin, arduino.LOW);
}
void draw(){
if (mode == "file" || mode == "radio"){
beat.detect(song.mix);
drawWaveForm((AudioSource)song);
} else if (mode == "mic"){
beat.detect(in.mix);
drawWaveForm((AudioSource)in);
}
if (hasInput){ //hasInput is set within drawWaveForm
for (int i=0; i<displayNum-1; i++){
if ( beat.isRange( i+1, i+1, 1) ){
shiftWrite(i, 1);
lastFired[i] = millis();
} else {
if ((millis() - lastFired[i]) > minTimeOn){
shiftWrite(i, 0);
}
}
}
}
} //End draw method
//Display the input waveform
//This method sets 'hasInput' - if any sample in the signal has a value
//larger than 'tol,' there is a signal and the lights should flash.
//Otherwise, only noise is present and the lights should stay off.
void drawWaveForm(AudioSource src){
background(0);
stroke(255);
hasInput = false;
for(int i = 0; i < src.bufferSize() - 1; i++)
{
line(i, 50 + src.left.get(i)*50, i+1, 50 + src.left.get(i+1)*50);
line(i, 150 + src.right.get(i)*50, i+1, 150 + src.right.get(i+1)*50);
if (!hasInput && (abs(src.left.get(i)) > tol || abs(src.right.get(i)) > tol)){
hasInput = true;
}
}
}
void resetPins(){
for (int i=0; i<ledPins.length; i++){
arduino.digitalWrite(ledPins[i], Arduino.LOW);
}
}
void stop(){
resetPins();
if (mode == "mic"){
in.close();
}
minim.stop();
super.stop();
}
BeatListener
class BeatListener implements AudioListener
{
private BeatDetect beat;
private AudioPlayer source;
BeatListener(BeatDetect beat, AudioPlayer source)
{
this.source = source;
this.source.addListener(this);
this.beat = beat;
}
void samples(float[] samps)
{
beat.detect(source.mix);
}
void samples(float[] sampsL, float[] sampsR)
{
beat.detect(source.mix);
}
}
You can achieve the same thing using standard bitwise operators. To turn a bit on:
data |= 1 << bitNumber;
The right-hand side (1 << bitNumber) is a bit-shift operation to create a suitable bit-mask. It takes the single '1' bit and moves it left until it reaches the desired position. The bitwise-or assignment (|=) combines that new bit-mask with the existing bits in data. This turns the desired bit on, but leaves the rest untouched.
The code to turn a bit off is slightly different:
data &= ~(1 << bitNumber);
You can see the same bit-shift operation here. However, it's preceded by the unary negation operator (~). This swaps all the 1's for 0's, and all the 0's for 1's. The result is the exact opposite of the bit-mask we used before. You can't do a bitwise-or operation this time though, or else you'll turn all the other bits on. The bitwise-and assignment (&=) is used instead to combine this mask with the data variable. This ensures the desired bit is turned off, and the rest are untouched.
In your code, desiredPin is the equivalent of bitNumber.
A full explanation of how bitwise operations work can be quite lengthy. I'd recommend looking for a good tutorial online if you need more help with that.
There are also the bitSet and bitClear Arduino macros that make the code a little more readable than bit shifting and using AND and OR. The format is either bitSet(what_to_modify,bit_number) and bitClear(what_to_modify,bit_number). These translate into very efficient code and can be used to manipulate both, variables and hardware registers. So for example, if you wanted to turn on pin 13 on the Arduino UNO, you would first need to look up that Arduino pin 13 is actually pin 5 on PORTB of the Atmel atmega328 chip. So the command would be:
bitSet(PORTB,5);