Yeah right, you might say. First PCB? Aren’t you an EE? Yeah, but I never woorked as an EE, and thus far anything I built for myself I just point to point wired it.
Frankly, I could have done the same here. But I wanted to see how this goes before starting a more complex circuit (which I already have a schematic for). This one is super simple, actually, it’s a programmer for ATMega 328P micros, which will be in all my other circuits. With a nifty ZIF socket for the chip to be programmed. It’s basically the same as the one I made for ATTiny85’s, except that one I hand wired on a protoype shield to plug into an Arduino Nano. The ATMega programmer firs an Arduino Nano on the board to be the driver.
Assuming it all checks out, in a week or soo I’ll have 10 boards. I only need 1, so if they are good I guess I’ll have 9 boards for anyone interested. Not selling anything, heck it only cost me $2 for the 10. The schematic comes right from an Arduino sketch included with the IDE as an example - it’s the Arduino as ISP sketch. I used EasyEDA for this one, since they are tied to a large parts supplier as well as a board maker, and they have libraries and footprints for every part they sell, though in this case I don’t need to buy any components, I have plenty of everything on hand. Since my project is on EasyEDA, and I made it public, anyone can go take a look. Use this link (I think)(you might have to sign up to actually open anything - it’s free though, sorry)
https://easyeda.com/megaslug/Atmel-Programmer-using-ArduinoISP
Next up, if this proves successful, will be my turnout controller. I have some mods to make to the schematic because I figured out how to use the same circuit to control 2 turnouts via central control or 3 using only local control, so I can use the same circuit for the mainline dispatcher controlled turnouts (with local control buttons that
While I don’t have the knowledge base and understanding you have in EE, Randy, I did work as an electronics tech for nearly 4 years and enjoyed wiring/ski wiring and repairing prototype PCBs. Yea, 0402 & 0603 resistors and caps were regular items on the menu for me.
I’m looking forward to seeing how this project turns out. And I hear what you are saying about sharing your knowledge/projects with other modelers. That’s part of the enjoyment of the hobby for me.
Tom
Boards arrived today. They look good, have to see if I got it all correct when I wire one up. Hopefully over the weekend.
–Randy
Doh! Was SURE I had some female header pins around - but no. I don;t want to solder the Arduino Nano right to the board, if something goes wrong it will be a real pain to desolder 30 pins (one of these days I will get a proper desoldering station - I should just order the darn thing, it actually is a 3 in one, pencil iron, desoldering vacuum gun, and a hot air gun - this would relegate my existing soldering station to the railroad bench).
So luckily there are many packs of female headers on Amazon with Prime shipping, so I will have them Friday.
I STILl think I have female headsers somewhere - why I woould have ever bought them escapes me. I found my supply of male straight and right angle, and 2x3 (for ICSP headers on Nanos). I need to lable my stoorage bins - I have most of my parts and subassemblies inventoried in a really neat onine inventory system, just don;t have all my resistors and caps in it. No female headers listed as in stock there, so maybe i was just dreaming I had them.
–Randy
And …
It works!
Took a little fiddling to get the settings all correct to program an ATMega328P, but once I got it all set up properly, I was able to program both of the extra chips I had. No modifications needed to my circuit on the board, just solder in all the parts and it worked.
–Randy
Polychlorinated biphenol (PCB) is a hazardous oil used to cool electrical transformers and electrical equipment.
And PCP is a dangerous drug - what does that have to do with circuit boards? [(-D]
PCBs are why there are no operational GG1s. All those on display have had the hazardous materials removed.
–Randy