I am a beginner to arduino and trying to follow one of the videos from youtube to make a project- Master And Slave using HC-05 modules. I followed every step from that video carefully. Here's the link to the video ->
https://www.youtube.com/watch?v=BXXAcFOTnBo
For Slave Module when I type AT commands in the serial monitor nothing shows up.
I searched in Internet for the this problem and still didn't fix it. Here's What i have done:
tired restarting my pc
tried Changing arduino, At first i used arduino nano and then uno
I tried changing the baud rate to all other values and nothing happened
And there is no change in light blink, it stays on AT command mode until power is turned off and on again.
This is how is looks
Thank You For the Answer
Your problem is not actually related to arduino in any way. This tutorial is utilizing onboard USB->UART transceiver IC. So in theory you could even remove Atmel chip from the board. Its more like using module like this FT232 converter. Anyways sorry if I confused you but you can research the subject.
But anyways to the problem. Couple of questions:
Did you press reset button on module while powerin up the circuit?
Thats the way it enters to AT command mode
Did you try to reverse RX-TX lines, don't worry connecting these guys across eatch other doesn't harm your board.
(They are so often plugged in wrong..)
Did you make sure you have connected EN pin of module also. (To arduino 3.3V not 5V)
Did you triple check all connections
Try to upload simple Sketch like blinky to Arduino to make sure you are connected to USB-UART transeiver and you have correct drivers.
Make sure you upload empty sketch or remove the chip when you try to apply tutorial steps.
Change jumper wires. Sometimes cheap jumper wires are really bad quality.
I have been sometimes scratching head for long time because of broken jumper cable.
Please let me know if you have checked all of those so we can think for next step.
Related
Let me start off with the components used:
GPIO extension board to connect the raspberry pi to components
Bme280
Pi 3B
Problem description:
This problem was intermittent at first. We were receiving reading and the error occured out of nowhere, made adjustment to the sensor(taking out and putting it back in) which solved it but when we touch the sensor the error showed up again.
We decided to change the sensor and the problem turned from intermittent to persistent. Now we have this as permanent issue.
We removed the package for BME280 and SmBus2 and decided to reinstall it again.
RPI Bme280: https://pypi.org/project/RPi.bme280/
I followed this BME280 installation guide, however when prompting for 'i2cdetect -y 1' there were lines but no number showing up.
What has been confirmed so far:
Patching up of circuits was fine, tested with my lecturer pi and it
works fine.
Codes is fine, we even use the sample code provided by RPi.bme280
I2c was enabled everytime
Please help me because I am really lost. I needa submit this by next week so any help is appreciated.
Problem pic --> Picture of the problem
I've tried to respond, but there is a few pitfalls in SMBus and i2c, so to break the question into smaller bits I've quoted your original message with an indent. The response is provided beneath.
This problem was intermittent at first. We were receiving reading and the error occurred out of nowhere, made adjustment to the sensor(taking out and putting it back in) which solved it but when we touch the sensor the error showed up again.
I locked onto the statement, "Touched the sensor". Is there a chance the BME280 experienced an ESD discharge? And therefore is now partially or fully broken?
Are you using an ESD safe room? or at least ESD bracelet. You will not notice small ESD discharges, and for small electronics even a sub 1000V discharge can cause damage instantly or over time. (Fundamentals of Electrostatic Discarge - incompliancemag.com)
I followed this BME280 installation guide, however when prompting for 'i2cdetect -y 1' there were lines but no number showing up.
The I2Cdetect -y 1
Will send a ReadBit message to each possible slave 0-127. Then listens for the ACK on the slave address.
The message is very simple, but does the trick for detecting working i2c slaves.
As you stated there is no "Lines", i would suggest the slave either has issues responding, if the BME280 has the correct 3v3+GND supplied.
As another possability, could you redo this step dtparam=i2c_arm=on,i2c_baudrate=400000
(Set the baudrate way down to 10000 /10k. Should this solve the issue and you need higher bandwidth, attempt on "50000 /50k" or "100000 /100k") This is just to eliminate the possibility the slave cannot opperate on this high frequency. 400k Baudrate for SMBus is high for a prototype/testing scenario. Very small amounts of interference can corrupt the data over SDA.
Another possibility is the Sink-Current which i've learned the hard way is not the same on i2c and SMBus over i2c.
Is you Pull-up resistor appropriate for the limited sink-current?
The SMBus specifies a minimum sink current of 100µA, and a maximum of 350µA, compared to 3mA for the I²C bus (Ampere=Voltage/Resistance Ohm).
Now to the Software issue.
From your supplied picture on imgur.
File "newcodes_''''''''''''''.py" line 2, in
Your compiler cannot find "bme" where you attempt to import bme280. Reference/path issue?
This can be the cause for other issues further into the code calls.
I don't know what SW you are writing the code in, but if there is an option to insert a breakpoint and run a debug build. I would suggest starting there :)
Alright I have resolved the issue, I changed the wire from jumper wire to hard wire. Thank you guys for your response. I appreciate all of them :D
I am using the instructions of https://pimylifeup.com/raspberry-pi-rfid-rc522/ to learn how to read my rfid-rc522.
I installed all the things needed, and cloned from git all the files. I connected accordingly and double checked the wire.
The code in Write.py is
#!/usr/bin/env python
import RPi.GPIO as GPIO
import SimpleMFRC522
reader = SimpleMFRC522.SimpleMFRC522()
try:
text = raw_input('New data:')
print("Now place your tag to write")
reader.write(text)
print("Written")
finally:
GPIO.cleanup()
When I run it- The result stops after "Now place your tag to write" and nothing happens when I place my tag. Any help please? What's wrong here? The module gives red light meaning it is connected. Is it really connected? How do I know? Please help.
Edit: My title and tags were wrong in this question due to already saved data. I edited. :)
It can be multiple reasons why your reader is not retrieving any data:
The RFID cards that you are providing to the reader are not supported by the ISO 14443: Mifare Classic, 4K. (Some DesFire, etc...) are the cards you want to try. Source: https://en.wikipedia.org/wiki/ISO/IEC_14443
The MFRC522 is not receiving enough input voltage. Try to increase from 3.3V to 4V. I have tried with 5V months and the reader is still running perfectly, but be cautious. The safe range in NXP is from 2.5V to 3.6V. Source: https://www.nxp.com/docs/en/data-sheet/MFRC522.pdf
The library you are using does not support IRQ (Interruption Request). This means the process of reading UIDs is high CPU consuming and low in performance. Try to use this popular library which supports interruptions: https://github.com/ondryaso/pi-rc522 . You will need to connect another wire from the IRQ pin in the MFRC522 to one GPIO pin in the Raspberry that is free and supports reading/writing operations.
Check if SPI interfaces are enable in Raspbian. Open a terminal and run:
ls -l /dev/spi
Lastly, it could be that your reader is broken. Some chinese versions do not work as they should do. Maybe you should buy another one and try more luck.
I suppose you have connected all cables in the correct way between the MFRC522 and the Raspberry Pi. Check that again.
I have a HM-10 (probably a clone) which I managed to get into AT mode quickly (by shortening 5V and GND prior to connecting it to the ESP8266 where it's running on), and I can configure it, but I just cannot get it out of AT mode. AT+RESET gives me "OK", but contrary to my HC-05, it doesn't switch from slow to fast blinking and is also not discoverable from my MacBook.
I have tried AT+ORGL and AT+RENEW as well, but to no avail.
Does anyone have an idea how to get it working again? Because this way, it's kind of bricked.
Also, is there a way to make the device have a four digit pin only? When I use AT+PIN0000 it returns ERR, only when I use AT+PIN000000 it returns OK.
Having a couple of issues with what I was hoping to be fairly straight forward.
I've been transmitting data from my PIC to a PC via RS232 at a baudrate of 115200. I've recently got a RN-41 bluetooth module and was hoping the switch would be as simple as powering the module and connecting the PIC TX (via a max3232) to the RN-41's RX, as the online community has led me to believe.
I'm able to connect to it and pair it to the computer, I'm also able to use PUTTY/Realterm to change the parameters, like the name and baudrate. Finally, by connecting a link to the RX and TX on the bluetooth module and powering it, I'm able to ping text by sending and echoing it using PUTTY, so I'm fairly sure the module isn't broken.
However, when I try to transmit my data from the PIC to the bluetooth module, and view it using realterm (which was working fine with the wired connection) I'm getting data received, but it's not what is expected. I'm expecting a packet of 25 bytes, with a header value of 2, I'm getting around 12-15 bytes and a header of -65.
The first value, -65, is always the same, and the other data can change, which really suggests a baudrate problem, but I've tried a variety of baudrates (changed in my UART code, the bluetooth parameters, and in realterm), and the data doesn't change at all; always wrong.
What have I missed? Anything I need to change in the Bluetooth configurations? I've also checked the parity bit, stop bit, etc, all the same as each other.
The problem was the MAX3232 circuitry. It was necessary for the RS232 connection I was using prior, but when I wanted Bluetooth, which required TTL signals, I was feeding it the same RS232 data!
Making a link straight from the PIC to the Bluetooth receiver solved this problem. Hope this helps someone else in the future!
I have a telephony modem which gives voice to my interfaced application via a serial USB ttyUSB0 in 16bit PCM 8000hz. I am able to capture this data and play with audacity. I want this port to be detected as a sound device in linux (I am on ubuntu). Is it possible? Are there any other options?
I'm guessing you are using a huawei 3G modem or something similar which gives ttyUSB1 for audio. Make sure you have the serial driver binded to it. Then simply pass the port itself as a "file" for input for any program of your choice.You need root access for that.You figured out the audio settings so it must be enough.I have voice calling working in UBUNTU 11.10 with Huawei. So let me know if i can help any further.
Ok, I see it's very old question but answers helped me to get a right direction so I decided to help others.
The one way to achieve (in addition to below) what are you are
looking for is to write dynamic kernel module.
Have it register as a sound device, and check that it has a GSM
module present (which module is it exactly can be recognized in
dmesg, lsmod, or output).
Then establish communication between user space representation as a
sound card and serial usb module.
The other way is to get module that you recognized by dmesg, lsmod and extend its functionality as a sound card.
All are tricky tasks because:
in the first case you have to resolve intermodule communication at the kernel level...... which is, lets say, a little hard even if programmer has a right background in subject.
the second case is hard in that you have to deal with:
USB stack (which is little unpleasant for human beings) and
sound subsystem (which is a little burdensome because of historical issues).
Without being an experienced kernel programmer there are small chances to succeed.