petercl14

Hi Harry, Problem fixed. The usb to serial device I received had a switch which wasn't on the device shown in the project. Also had a dtr pin not on the project. This meant data received. I connected it the same as the rts pin in the project with the capacitor connected to reset pin on MCU. No problem with this. The problem was the switch apparently as this was set to 3.3v. When I connected to 5v and used uno as the program, the download worked. Now will be able to use jaycars zz8727 in many projects. Thanks for your interest.

Hi Harry, I have already looked into all those references. I think I must have the wrong port. I have seen one reference where burning the bootloader you use a com 18 port. I don't have to burn a bootloader as the atmega 328p already has a uno bootloader preinstalled.When you pick the programmer you always seem to get a com port that goes with it. Perhaps I should be looking for the programmer with a com 18 port? I have also seen a reference where you take out the MCU from the uno board and replace it with the MCU you want to program. The idea of this is that then you can use the USB to serial converter on the uno board. But in the project from electronics lab you have a converter so you don't have to do that. And another problem is in removing MCUs with so many pins as it is so easy to bend the pins. Please let the author of the project give more details. He makes no mention of the program to use.

Hi, Can't get this project to work. Not uploading. I am using atmega328p mcu ic with arduino uno bootloader from jaycar. cat zz8727. Using uno com3. What is the programmer? Tried avr isp, avrisp mkll, arduino isp, arduino as isp. None of these work to upload my program. Can anyone help?

Hi Harry, none of those circuits are the one I posted with the pnp transistor connected to the gate. I was hoping somebody could explain how that circuit works? It doesn't look possible. It is the circuit you also posted asking for 1 amp or 100 amps. I suggested 1 amp. Do you or anybody else on this forum know how it works?

Hi Harry, I would never use this circuit myself. A triac optocoupler is much better. Either phase control(random) or zero crossing. The thing is the circuit is from a book called Power Electronics by a professor of Electrical Engineering at Edinburgh university in Scotland. So the circuit must work. What bugs me and I hope you and others on this forum also is how does it work? It would seem to require a reverse current to the pnp. Lets say 1 amp load, 240 resistor for R2. The text doesn't explain how it works. It gives this much. R5 is to stop the triac turning on falsely. This resistor is to drain a capacitor effect at the gate. I don't know about you but for me I don't like to leave the puzzle of how this works unsolved. It is in our nature. So if anybody knows on this forum please let us know. Thanks for the triac reference Harry. Also no triac optos on LTSpice.

Anybody got any idea how the attached electronic circuit works. It appears you would need a reverse current through the pnp transsistor. If somebody knows and would kindly add resistor values I can test it in a spice simulation. The circuit is from a textbook on power electronics. power electronics triac gate drive circuit.asc

Hi Harry, Did I mention that I am using a 'usb to serial/ttl adapter' connected to a duinotech atmega 328p mcu with an already installed uno bootloader. Both items purchased from Jaycar. The upload seems to go ok but never finishes. Finally I get message 'programmer not responding, not in sync'. Another message was 'can't find file referred to'. I think you are calling the adapter a FTDI. I have been trying to upload the 'blink' example as in the article. Like everybody else I like to get to the bottom of why something is not working. Not satisfying when you can't. Had some trouble installing the mcu on my solderless breadboard because of the large number of pins. Had to bend them in a bit. Looks like I may just have to use the uno board to program the mcu and then remove it from the board if I want to use it in a circuit. Of course an embedded mcu is the way to go but I don't have the technology to do that. The program on my nano board is now a mass of wires and switches and hardware. What the program does is quite marvelous but I wont go into that as I will be applying for a patent on it. A manufacturer will need a custom PCB to contain an embedded MCU as on my nano board.

Hi Harry, You asked me what I am trying to do. I have connected everything as in the article. I am trying to program an atmega 328p which has a uno bootloader installed. This MCU is from Jaycar electronics. All the articles I can find talk about burning a bootloader. But if the bootloader is already installed you don't need to burn one. Anyway I tried uploading the Arduino blink example as in the article. The upload never finished. I had this same problem in the past when I didn't have 'old bootloader' selected. The upload never finished. I am thinking that I may have to find uno bootloader somewhere on the arduino ide for the upload to work. Any suggestions on how I could somehow use the uno bootloader? The programs I want to upload were all worked out on a nano board. I don't know if that has anything to do with the problem. Perhaps if I had done the sketches on the uno board I wouldn't have the upload problem.

Pretty sure now of the problem I have downloading to the atmega 328p from Jaycar with the uno bootloader. I have been using the nano board.I do have the uno board but didn't like it as you have to plug in a lot of wires to use it. I have been using the nano board for a long time now as you can plug it in directly to a solderless breadboard. Tried picking uno board in tools menu. Didn't work. It appears then that my only option may be to use the uno board as it has the uno bootloader. Is that all I can try now? Didn't actually notice before that the Jaycar atmega 328p used a uno bootloader. Could there be an option in tools somewhere to use the uno bootloader but retain the nano board?

Hi, I am trying to program the Atmega 328p microcontroller from Jaycar. This is the one they say has a bootloader. I have made all the connections as required in the article. I am using com3 which I presume is a port on my laptop. I am trying the first option and not using the Arduino nano board. The download is not working. "cannot find file specified" error. I am not sure at all what the port is the article talks about. Also don't know what board I should be selecting. The program I want to download has been conceived and tested on the Arduino nano board. But as I am not now using this board I can't see that this is correct in selecting a board. Could somebody please clarify what is meant by 'port' and 'board' in this article. Also my usb to serial/ttl board from Jaycar has a switch on it not mentioned in the article. What is the purpose of this switch? Programming Atmega328p Microcontroller with Arduino IDE - Electronics-Lab.com.html

Thanks Harry. When I pick Duemilanove on the board manager I get at the bottom of my screen Duemilanove on com3. Previously it was nano on com3. My arduino nano board. So that looks sweet. The port is mentioned. This is without connecting the adaptor board as you suggest to get the port. Hoping I will get the same port mentioned when I connect the adaptor board so that I wont have to change the com.

In this scenario I am programming directly to the atmega 328p through its bootloader. I have already programmed the 328 and tested the code by programming to the nano board. Then looking up the board manager on the arduino ide I see mega and mega 2560. Could this mean the Atmega 328p for direct programming? I sure wish the author of this article could have given this further info to be able to program directly to 328 through its bootloader. The very good schematic with this article shows the connections from the 'usb to serial/ttl adaptor' to the 328. Another problem I see is that the port reference is faded out in my IDE tools menu. So I can't enter a port.

The article provided a way to program the 328 without using an arduino board. Several things I didn't understand about downloading. It says to name the port the 'usb to serial/ ttl adaptor' is connected to. What port would this be? Also it says to name the board type. What is the board type? And where do I put these things in on my computer? I have not seen the previous article about getting a bootloader onto the 328. I have found a 328 available at Jaycar that already has the bootloader installed. Can somebody give me the answers to the above. Perhaps the guy that wrote the article. Thanks in advance.