USB programmer for beginners
USB programmer for beginners
Now we will assemble a USB programmer for beginners (beginner radio amateurs), most will say this is a complex circuit, let’s start with LPT, but I want to say that the circuit is very simple, and you only need to program it once and don’t worry.
Programmer circuit diagram
As you can see from the diagram, there is no quartz resonator – this is the trick of the diagram. I made a not very compact programmer, if you want you can make it smaller, and if you have double-sided textolite, you can shove it into USB, so it will be completely unnoticeable. And now a small photo session.
But first, the USB layout:
I forgot to say that first you don’t need to program RSTDSBL, but program CKSEL3, CKSEL2, CKSEL1 and connect to the PC. If the computer has found an unknown device, it doesn’t mean anything, the driver should be installed. After that, you can program RSTDSBL, since the number of pins on the microcontroller is limited. By the way, you can use ATtiny45 or ATtiny85. The main thing is that there are 20su in the SMD or 20pu in the DIP. For example, ATtiny45 20su. There was no ATtiny45 in the store, but there was ATtiny85 20su. I programmed it the same way as ATtiny 45 and the fuses are the same. They only differ in the flash memory. The fuses that need to be programmed are CKSEL3, CKSEL2, CKSEL1, BODLEVEL0 (low voltage detector at 1.8 V), RSTDSBL.
You can use any connector – there is a micro USB and the like, I didn’t try to be clever, I took a USB plug, peeled off the skin, filed it down, soldered it and got something that looks like a regular flash drive. We trim it with a stationery knife, but be careful not to cut yourself – the blade is very sharp.
We take out the plastic part with contacts, also very carefully.
Let’s take it and file it down so that the soldering iron tip can reach the USB contacts. There is already an etched board for the USB programmer on top. I etched it in hydrogen peroxide + citric acid. It etches quickly.
I tinned the board. I haven’t got hold of Rose alloy yet, so I tin it with a soldering iron tip. For tinning, I threw a stone into the rosin solvent, stirred it, the stone dissolved, I put it in a syringe (I don’t remember the proportions), covered the board and it’s very convenient to tin. We solder our plastic, just don’t mix up the contacts when soldering, otherwise, as I will re-solder, it’s wrong in the photo below.
Next we solder the resistors and the MK, here I saw an error and re-soldered the USB, the connection cut should be on the same side as the controller.
The other side – the zener diodes should be no more than 500 mA.
We solder the ribbon cable, it is desirable that the ribbon cable be shielded, I used a cable from a card reader, I took shielded wires – two orange and a screen = foil thrown to the ground, a photo without a case, you first need to check for operability, the torus program is connected ATtiny2313A was flashed soon, I flash at a frequency of 250 kHz, and fuses at 2 kHz – it is more reliable.
I had nothing to make the case out of, I had no extra flash drives, no broken modems… the answer came by itself – a lighter, release gas if there is any, spray, this type of lighter is initially different, a photo of the lighter because I already sawed the first one, but forgot to take a photo.
We break out the middle wall, push in our programmer, secure it with hot glue, and before final securing, adjust the position of the board.
And this is what happened.
