is it possible to upload a firmware to an ATMEGA328P aka Arduino Uno using a serial terminal like Putty or Coolterm?
I know that the Arduino is ready to receive a new firmware after a reset over USB, does the IDE (and avrdude) makes something different other than echoing the binary hex file over serial port?
Thanks
Theoretically, yes. It would be awkward, and you'd need to be able to send and receive arbitrary bytes within a strict time limit, before the bootloader gives up waiting, but you could do it.
The most common bootloaders for the atmega328 use Atmel's STK500 protocol, originally designed for their own AVR development boards but widely used elsewhere (such as on the Arduino). Documentation for this protocol can be found here.
Note that Optiboot, used on modern Arduinos, implements only a subset of this protocol.
Related
I am using an ATtiny85 8 pin AVR to send AT commands to an RN42 Bluetooth module. I am programming the AVR using an Arduino as an ISP therefore writing the code in the Arduino IDE, using the SoftwareSerial library as the AVR has no UART port.
To ensure accurate clocking out of the data I have added an 8MHz oscillator (LFSPXO018045) on pin 2 but I'm not sure how to make sure the AVR is using this and not just defaulting to the internal osc. I've seen mention of "Fuses" that need setting? Is there any in-code things I need to do like set a register flag or any pre-scalers?
Here is the Eagle circuit and option I found so far but don't know if there's anything else that needs doing too?: PCB & IDE
By the way this is my first question so please be lenient if I've missed something!
Clock settings of AVR MCUs can be changed via using the dedicated Fuse bits. These Fuse bits unfortunately cannot be modified from software. The only way to program the Fuse bits is either using a JTAG programmer or an ISP programmer (like: USBasp, AVRISP mkII or you can use an Arduino as an ISP programmer with the right sketch on it).
This AVR Fuse calculator tool can be used to determine what settings and Fuse values you need to program.
Please pardon me if this question comes as a little too basic but I have tried searching almost everywhere but haven't found a clue.
I am using the esp8266 module and have uploaded the firmware in it. I have also set it as "Access point" so that other modules are able to connect with it. My problem is that I want to control it pro-grammatically through an 8051 micro-controller. I have searched online and there is a lot of documentation on how it program it through arduino, but that doesn't solve it for me. I want to use assembly language to build a serial protocol that communicates the data from 8051 to esp8266 and then to the connected modules (such as Android device).
My question really is, "would it be possible to just connect TX/RX of 8051 to RX/TX of esp8266 and write a code in assembly that transfers data as I desire to esp8266? Or, do I have to do something else?".
At the moment the only documented way for a host controller (the 8051 in your case) to talk to the ESP8266 is to use the serial port (there is a slave SPI port but the mechanism for driving it isn't known yet). So you will have to make up a little protocol to send and receive commands and data (assuming that the standard support for an enhanced AT command set isn't sufficient for you).
The baud rate can go a lot higher than the default 115200bps, if you need it to (although I'm not sure if the 8051 could keep up).
I downloaded several software that provide virtual COM ports. These COM ports do appear in the Device Manager and can be selected for upload from the Arduino IDE, menu Tools -> Serial Port -> COM3. It starts uploading and reaches 90% and then it either times out or just does nothing.
I want to upload onto the virtual COM port so I could then read the compilation output files in another program. I don't want to use my Arduino at all, and I don't want to manually get the verbose output files when uploading. This problem doesn't happen when I upload on the real Arduino.
The application should work on all platforms. This task seems easy on Linux, and I am facing the stated problem on Windows and any help with Mac would also be useful.
The application will be an educational tool for hardware simulation and visualization trying to give a more hands-on experience for users than other simulators out there. So may be this will give you an idea of why I want to do so.
How can I get started?
I think you might be assuming that uploading code to Arduino is one-way communications: this would be like putting strawberries in a blender, and a Daquiri comes out. If that was true, you could just take whatever the IDE dumps to the serial port, save it to a file, and you have an Arduino binary. (Skip to TL;DR if not interested in details. Upshot: this assumption is not correct).
The 1-way communication assumption is not entirely correct: there is a program on the Arduino (called "a bootloader") which is responsible for communicating with the programmer ("programmer": a program that programs the Arduino, assume it is the Arduino IDE for now). In their most "natural" state, the Arduino CPUs cannot be programmed across serial lines. Rather these chips are programmed either via the in system programming (ISP) or via the JTAG protocol. The bootloader is a program that runs on an Arduino CPU and loading of sketches/programs over the serial port. This program runs at startup and looks for programming commands over the serial port.
If it discovers that a programmer is trying to communicate programming information, it will read the compiled Arduino binary coming over the serial link, store it in flash memory, send it back to over the serial link for verification, and if everything is successful, exit and launch the stored sketch. If no programming information appears on the serial port, that is, no programmer is trying to write a new sketch, then the bootloader simply quits and launches the program already stored in flash.
TL;DR: In order to implement a pseudo-Arduino on your serial port you must write a program some code that simulates an Arduino (bootloader) on the other end of your virtual serial port. So when a programmer/IDE says to Arduino "are you there?" your program will respond "yes!", just like an Arduino would.
The default Arduino bootloader is STK-500 compatible: that means that it implements STK-500 commands - the reference for which can be found here. If you decide to do this, then the easiest thing might be to start with an existing bootloader, such as Arduino's or AdaFruit's (there are others too), and modify it. Such a bootloader would have all the commands already implemented, and since it is written in C (I wouldn't choose an assembly bootloader to modify :), it should be easy enough to modify.
Alternatively, you might decide that STK-500 is too difficult to implement. If this is the case, you can use any programmer protocol that Avrdude supports: Avrdude is a program for programming AVR chips, and Arduino IDE uses Avrdude internally to send the sketch to the Arduino. If you do this, then you'd have to change the settings in Arduino IDE for which programmer you are using.
Personally, I think STK-500 compatible is the best option for this, but YMMV.
How can I send a string via serial communications from Java or Python? I have a very little arduino program that will recieve a CSV string of ints that each control different relays (I adapted it from their example).
I just got an Arduino, and I am trying to use it to open and close a relay remotely. I have it opening and closing the relay, no problem. But I really have no idea where to start as far as using serial communication.
I have a bluetooth dongle that I can connect to, but once I do that I'm lost.
Also, this is my first time using serial communications AND my first time using an Arduino. So I'm sorry if I am completely off on some of the things I am asking. All I know is what I've learned from Google.
Thank you very much
You can use any Java or Python serial port classes and methods. There is however one thing you need to be aware of.
The newer arduino's have a feature known as AutoReset. This works by connecting the DTR signal from the serial port to the Reset line on the chip using a capacitor or such. The IDE uses this to reset the board to activate the bootloader and initiate uploading code to the arduino. The serial monitor in the IDE is aware of this and does not toggle the DTR line when comunicating with the device (except when it initially connects).
There is are several ways to defeat this feature and you can read about them here.
As for actually comunicating with the device, there are several tutorials about serial communication in both Java and Python.
Pyserial includes the option to not use the DTR lines when opening a port.
Here is a website explaining how to use RXTX (a Java library) to comunicate with an Arduino
Best of luck.
I'm using an Arduino to read data from the web and display it. I can easily pass the data as serial using the supplied drivers, because they identify the COM port so I can send serial to the COM port.
However, I want to use 'real' USB techniques so the device can be plugged in and out like a normal USB device. I'm looking at using WinUSB as the driver. However, USB is all new to me. Is there an .inf file that uses WinUSB and an Arduino (I have an Uno)?
The lack of information on this is making me think I am going about this incorrectly.
Turns out that an Arduino Uno is not a genuine USB device.
It acts as a Serial to USB adapter. Consequently USB drivers don't talk to it.
I got round this by writing a sketch which reported back what device it was when it got the correct query from the PC.
On the PC I just iterated the Serial ports and sent the query to each port. The one that replied was the Arduino.
After that I record the port number and send serial data to the Arduino.
To learn the USB portion, maybe you could combine V-USB and the UNO?
Check out V-USB.
V-USB is a software-only implementation of a low-speed USB device for Atmel’s AVR® microcontrollers, making it possible to build USB hardware with almost any AVR® microcontroller, not requiring any additional chip.
While not necessarily Arduino, it may provide you the learning exprience you want, and let you use incorporate your UNO device.