Arduino UNO on breadboard with Serial Communication

Paul__B:

ralphd: I think the third option you forgot is the cheapest - the PL2303. ... I have a whack of these after I made a deal with Roman at dipmicro to take 70 that he was having problems with for ~25c ea.

So - what were these "problems"?

They were clone PL2303HX chips, and would give "Error code 10" if you used them in windows with the latest drivers. The error was only because Prolific figured out how to detect the difference between one of their own chips and a clone chip, and updated their driver so it would fail with the clones. The Linux driver is part of the kernel, and I'm sure a patch submitted to make the driver fail on suspected clone chips would never make it into mainline, hence the clones work fine on Linux.

Once you go back to the old version of the driver, they fine on windows too. I did most of the testing of my half-duplex software UART using the PL2303HX modules on a Windows 7 box. They worked great even at high baud rates. The old Windows driver has a bug that will blue screen the machine if you choose a baud rate of 9999999kbps, but who needs to use that baud rate anyway?

What really fascinates me is - where is the market for "clone PL2303HX" chips? It cannot be Arduino and PIC hobbyists or piecemeal project builders on eBay.

This suggests that these chips are in high demand, sufficient to make it worthwhile setting up a "pirate" chip fab. Beyond that, who is the manufacturer who is making and selling all of which products (using those chips), and clearly considers the "clones" to be of completely adequate quality to use?

Paul__B:
What really fascinates me is - where is the market for “clone PL2303HX” chips? It cannot be Arduino and PIC hobbyists or piecemeal project builders on eBay.

It’s the manufacturers of boards using the chips. The IP was probably copied, meaning little engineering would be required. They are probably produced on an old (and cheap) process node like .5 micron. Packaged and tested production cost is likely <5c in 1m quantity.

Can you share a schematic that I should implement please?

hbtalvi: Can you share a schematic that I should implement please?

You can come to the forums for advise, but don't expect anyone to design your project for you.

Sure - minimal design with MIKROE483 from Mouser for USB/Serial interface if needed:
http://www.mouser.com/ProductDetail/mikroElektronika/MIKROE-483/?qs=%2Fha2pyFadugsEwyLV5fFyIWdPbushEDhRSvnBE0ODG8%3D

ralphd:
It’s the manufacturers of boards using the chips.

And that was my point of curiosity - who are these manufacturers and what are these boards doing? What consumer or industrial appliance is made in millions quantity by a manufacturer who will choose “clone” parts over the primary suppliers?

ralphd:
Packaged and tested production cost is likely <5c in 1m quantity.

No doubt, no doubt. But so should the original, “reputable” chip fab.

hbtalvi:
Can you share a schematic that I should implement please?

The schematics are freely published on the Arduino site. Once you understand that schematic, you simply take as much of it as you need for your purpose. Nevertheless, given the price of the cheap Chinese “clones”, I feel it will be more practical overall, to either use a “Nano” module in itself or at least a USB to Serial module attached to your own ATmega328 board.

Paul__B:

ralphd: It's the manufacturers of boards using the chips.

And that was my point of curiosity - who are these manufacturers and what are these boards doing? What consumer or industrial appliance is made in millions quantity by a manufacturer who will choose "clone" parts over the primary suppliers?

I doubt there are any board manufacturers making products in the millions that use them, but I expect Prolific produces them in those quantities. Companies like LC Tech, Baite, D-Sun, etc could be buying the clone chips, and perhaps not even knowingly. http://www.lctech-inc.com/Hardware/Detail.aspx?id=cf719357-1046-4475-98e4-244f4c628a04

I agree it seems hard to imagine where all the chips can be going, but there is a surprising amount of embedded technology around. Things like USB POS receipt printers could have USB-ttl chips in them. I recently took apart an indoor air quality meter (temp, humidity, C02). It has a USB interface so you can plug it into a computer and log the information. Inside was an FTDI USB-TTL, and an ATmega328 (and a NDIR CO2 module).

sir, I have USB to TTL device Model# ch340g but not work properly because software problem. Can meet this software. sir give me that solve my problem.