I bought a genuine Arduino Uno from Maplins with the intention of
having a play with some stepper motors to make a mini CNC something
or other
I got cold feet when i started lookinto into max currents and voltages
allowed by the Uno. So i thought get some cheapy ones.
I bought 5 for less than the cost of the genuine one.
Maybe there is a reason why they are cheap? A quick test and just installed
the blink sketch. First 2 were fine, the 3rd one wouldnt install so moved onto
the next 2 which were again OK.
So not a driver issue, (win7 x64) tried in win7x64 VM also and also tried it in
linux mint VM. The 3rd one just would not take it.
avrdude stk500_getsync() not in sync resp=0x00
I tried to create a programmer using another Uno, using the ArduinoISP
sketch, but unlike a video i watched on youtube my pin 13 LED stayed on?
I tried to program the non working Uno with the upload using programmer
option and im pretty sure something happened it now blinks, which is odd
because i set the blink sketch to 2 rapid blinks?
Pretty sure the pin 13 LED stayed on solid previously?
I tried serial monitor and got nothing, but i also got nothing with the
working ones either so it must be me doing it wrong.
They're cheap because they're made in china, and they don't put any money towards the Arduino project. They just copy the hardware. That's why, if you're using lots of clones and unofficial boards, you should be a good sport and put some money into the can (at the donation link on the download page)
They also cut some corners - usually they drop the 16u2 that the official Uno board has as a USB-serial converter (which was a great idea in principle, but almost nobody reprograms the 16u2, and it's not a particularly good serial adapter), and instead use a normal serial adapter (usually a CH340G), and build quality is a little variable.
Several times, I've gotten boards without a properly installed bootloader (or without the right bootloader), which were revived by putting clean bootloader on them.
Normally when you reset a board with the optiboot bootloader on it, you see 3 quick flashes from the led, and if you're trying to upload, the computer will upload during that time (it should be autoresettign the board when you start uploading).
You could have a bad board though - if they were all from the same vendor, all the same batch and model, I'd be inclined to suspect a bad board (why would one board be different?). That is sort of the risk with the cheap boards - there is a higher DoA rate.
Yep, i did buy an original which i hope supports the project, and the cheapy clones have the CH340 chipset.
I had a bit of doubt about attaching the original one to unknown stepper motors salvaged from various computer and printer parts with unknown voltages.
It seems that using the original one to program it did do something. Originally im pretty sure the pin 13 led stayed on all the time. After my frst attempt using the ArduinoISP sketch and upload as programmer the LED flashed 1 second on and off which is odd because i changed the sketch to have quicker flashes?
I tried again and it's nowchanged to... led on for 15s then off 15s (repeats 3 times) then its off for over 1 minute and then repeats.
LED on the good one stays on after uploading the programmer sketch is that correct?
Slight change, connected them together again and i managed to program the blink sketch into it and its flashing at the correct rate.
I selected burn bootloader and that appeared to work also. put the blink sketch back on all good.
I thought lets see if i can write to it directly now and got a different code. 0x93 when left in Arduino as ISP and 0x20 when i changed it to AVRISP mkII.
The first line came up as something had changed? but i forgot to make a note of what it was exactly.
