Note: How to not get scammed with Prolific (PL2303) USB - Serial adapters - Page 1
Forum section: electronics / general

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: June 16, 2011, 03:51:37 pm
content: Prolific (PL2303) adapter is an common solution about USB to Serial port adapters.Even so the company gives their chips only to branded companies.And the latest Prolific driver, it does one identity recognition at the hardware too.If the Prolific chip in your adapter is a fake copy, the driver does not work with it.Currently this chip is also found on the Agilent USB -> IR modems.And probably in many other old modems that use IR communications like laptops or mobile phones.About the drivers age , the last made from Prolific was at 2007.Probably they work fine, and this explains the reason of why they do not update it.Windows 2000/XP/Server2003 (32 & 64-bit) WDM WHQL Driver: v2.0.16.166Windows Vista/7/Server2008 (32 & 64-bit) WDF WHQL Driver: v3.3.17.203http://www.prolific.com.tw/eng/downloads.asp?id=31Prolific has an warning about the fake chips in their website too.F.A.Q. third question.http://www.prolific.com.tw/eng/FAQs.asp?ID=50They describe it politely as chip validity and support.If you ever interested to get an such no-name fake solution from eBay,be my guest.But now, you do not have the excuse to say that you was not warned about it !!

author: oPossum
author_rank: Super Contributor
timestamp: June 16, 2011, 04:07:21 pm
content: The fakes are quite common in the cheap translucent blue USB to serial converters and some cell phone cables. Common problems are the drivers refuse to work (code 10) or they are just not reliable. The fake chips are usually COB packaging and the real ones are usually SSOP.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: June 16, 2011, 04:20:25 pm
content: Nice pictures, thanks mate ..

author: ivan747
author_rank: Super Contributor
timestamp: June 19, 2011, 12:20:45 pm
content: My fake USB --> Serial adapter works fine. It even has a level shifter. I was thinking about why there where so many "Prolific" chips out there, because they cost pretty much the same as other chips. And now I know they are all fake.

author: johnmx
author_rank: Frequent Contributor
timestamp: June 19, 2011, 09:30:16 pm
content: That’s why I only use my home-made converter. It uses a FT232RL chip and a MAX3241E. All original stuffIt has jumpers to select +3.3V or +5V operation and TTL or RS232 levels. It is a must for every electronic lab.

author: westfw
author_rank: Super Contributor
timestamp: June 20, 2011, 07:10:40 am
content: So Prolific added code to their driver specifically to detect counterfeit (or "compatible"?) chips and not work?(if they're detectable as non-official chips, then they're not exactly counterfeits, right? Although they're they are at least "leveraging" the driver compatibility?)That's not very friendly. Not that I could everbuyreal Prolific chips anyway. Chalk up another point for FTDI.(What's WITH USB/Serial chip vendors??!! Major companies (TI, SI, Cypress) seem to be unable to offer either chips that have firmware compatible with built-in drivers, OR host-side drivers for more than a single OS.)

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: June 20, 2011, 01:03:09 pm
content: @westfwMy explanation to your questions will focus on the what called as correct and healthy corporate cooperation.Prolific needs to protect them self's from all those counterfeit parts.1) Looses money from those.2) Their work it must be patented, and so they have to protect it.Secondly, needs to protect their own customers, that are brand-names recognizable in the market.Who they invest their money on buying the technology made by Prolific ,and resale it with their own products. ( As part of their own products )And even the software it self ( Driver) it is part of the Prolific property.The driver is very well made, and has even the option to change the COM port number ,so the device to become compatible with any communication software settings,and it does that with out even rebooting windows.In my eyes they do well about protecting them self's,because they have one healthy hardware and software solution,that it can be trusted by their corporate partners, and there is an warranty,that the End User will get something that really works and be happy with it.We had many conversations in this forum, about how to protect our own work,when it comes to the point our ideas to turn in to products.And it turned out that just the paper work its so costly,and that is very difficult for a single person to handle the costs.And I think that is also our obligation to protect the work of the others.If we like to be called as healthy thinking persons.

author: Unknown
author_rank: Unknown
timestamp: June 20, 2011, 06:31:04 pm
content: Quote from: Kiriakos-GR on June 20, 2011, 01:03:09 pmA patent is not a trademark in any jurisdiction I'm familiar with, you can't lose a patent due to dilution.

author: msraya
author_rank: Unknown
timestamp: September 19, 2012, 11:47:35 am
content: Hello!First, sorry for retake this old old post, but I have several fake adapters not working in my lab and I not want to trow it.Sorry also for the patent issue but I only want to make it to work with my Windows 7 installation.The fake adapters work with version 3.3.2.105 of the Windows 7 drivers. You can get it from here:http://www.usglobalsat.com/store/download/546/win_drivers.zipIf you cannot get the driver in the link, I can send you via e-mail. Only post a message to me.Thank You!Manuel

author: Amarbir[Lynx-India]
author_rank: Frequent Contributor
timestamp: September 19, 2012, 07:07:57 pm
content: Quote from: msraya on September 19, 2012, 11:47:35 amWell,i think the drivers on thier website are ver 1.7.0.Please check and confirm .These drivers do exactly that they do not work with fakes .I also tried one old driver and it worked with a fake .How the hell are we suppose to get a idea what chip is fake in the first place

author: mariush
author_rank: Super Contributor
timestamp: September 19, 2012, 09:22:55 pm
content: Well, this thread revival made me curious enough to open my own usb to serial adapter...I initially thought it would just come out of the flexible transparent plastic case but it turns out when they heated the two sides of the shell the cable got locked in place. So.. when I pulled the insides out from the jack, the voltage wire broke.It uses a Max211CAI but the actual usb-serial is clear, no markings on it. The double sided pcb has slots for the gnd mesh of the usb cable and what I think to be stress relief holes for the wires but the wires were soldered straight to the holes.I don't have time now to do it right, so I just added a bit of solder and re-connected the wires...ps. the adapter is auto detected as prolific ... it's a Pluscom USB to Serial RS-323 DB-9 Adapter Cable ... came with CD in a pretty nice clam shell packaging.Seller was safekom on eBay, probably this exact item :http://www.ebay.com/itm/USB-Serial-DB9-Pin-RS232-DB25-Parallel-Printer-Cable-GPS-PDA-1M-1-2M-1-5M-2M-/280895061033?pt=LH_DefaultDomain_3&var=&hash=item8710fad921

author: msraya
author_rank: Unknown
timestamp: September 20, 2012, 08:16:43 am
content: Hello Amarbir!![Quote from: Amarbir[Lynx-India] on September 19, 2012, 07:07:57 pmYou cannot get idea what chip is fake in my opinion. If you install drivers on Prolific web page and It show error 10, you get a fake, and you must get the driver 3.3.2.105....In the Prolific Page:http://www.prolific.com.tw/US/supportDownload.aspx?FileType=56&FileID=133&pcid=85&Page=0you can find the Windows 7 driver version v3.4.36.247 of 2012-8-1. They changed the file versioning only for the instaler and now it doesnt mach.I can confirm you the controller in the zip file link I post earlier is for windows 7 64bit and is version 3.3.2.105 from 27/10/2008 working for me in two PCs with a fake one USB adaptor.The installer is version 10.13. The installer First throw away any old or new drivers instalation.Then you must reboot the PC. Then you insert the adpator and It must work.If it doesnt work, you can go to the Device Administrator and change the driver in the button. You select driver in my PC and a list must appear showing you the installed drivers. Select the 3.3.2.105 version and It work for me.mariush. If you not have problems with drivers, you can have a genuine adaptor o a rehacked one, HI HI... Also the price is dirty cheap and the seller is in Europe, this is a plus.. Interesting adquisition. I Take note.GreetingsManuel

author: linux-works
author_rank: Super Contributor
timestamp: September 23, 2012, 11:46:52 pm
content: I used to hack the pl2303 'cheap dongles' to try to get arduino capable serial converters (needed a reset line; very hard to find that. dtr, I mean.)a few ebay units must have been fakes BUT they came with working drivers! I had to remove the real drivers (or, some set of windows drivers), use their driver and then the dongles worked. however, that's only windows; on linux I never needed 'different versions'. there is no such thing, really. there's a pl2303 linux driver and there aren't 'many of them' like there would be for the windows world.

author: shamikrudra
author_rank: Newbie
timestamp: April 19, 2013, 01:57:34 am
content: I have tested lots of PL2303 with new driver. they don't work but they are working with old driver.if any one able to run pl2303hx chip with new driver please upload an image of pl2303 so that we can know the chip marking, is it different from original one. I think prolific want to phase out their old chip so they are saying chip is counterfeit.

author: GEuser
author_rank: Frequent Contributor
timestamp: April 19, 2013, 07:53:44 am
content: I went through this just the other week , win7 64bit .If one looks in the downloaded folder after unzipping there is a chip checker exe that is separate and easily lets one know the version and whether is fake .I had troubles with the driver not loading when plugging in the usb gadget , it worked the first time everytime but when unplug it and later plug back in it would not load the driver , BUT LOL , I found out even after installing the new prolific driver it did the same thingBUT LOL all it was I did not do a restart .usbdeview-64 from nirsoft dot net is a good gadget to get rid of old usb drivers in real time and only small imo , I had 3 prolific ones listed .cheers all ...

author: shamikrudra
author_rank: Newbie
timestamp: September 15, 2013, 06:10:58 pm
content: Must read for New PL2303HX userAfter lots of research I found that PL2303HX driver problem is mostly caused by two different version driver from prolific or from cable vendors. So if you find Error 10 please remove all the drivers for PL2303 then restart the PC then connect the device so that PC will ask for driver and install it.I have used different PL2303HX chips and all are working with latest Prolific drivers.PL2303HXLF = Lead Free then (Month-Year)date stamp then lot.

author: casper.bang
author_rank: Frequent Contributor
timestamp: September 18, 2013, 10:34:18 am
content: I've worked with both Prolific and FTDI, and the latter sure seems to win when it comes to driver issues and signal fidelity. However, I no longer use these discrete cables, since you can buy tiny US$7 FTDI break-out boards with 3.3V/5V selection jumper - very handy.

author: amyk
author_rank: Super Contributor
timestamp: September 18, 2013, 10:47:15 am
content: That looks more like a difference in the charge pump/level converter than the chip itself (which should just output plain TTL.)

author: andtfoot
author_rank: Unknown
timestamp: September 23, 2013, 03:54:01 pm
content: I was pulling apart one of these adapters recently and found something odd. There was a 0R surface mount resister soldered across the top of the crystal.I forgot to to take a photo, so here is a quick mock-up of what I mean.Anyone seen anything like it?

author: SeanB
author_rank: Super Contributor
timestamp: September 23, 2013, 05:56:01 pm
content: Soldered there to hide the marking on the crystal so you would never guess it was a 4MHz unit.

author: SeanB
author_rank: Super Contributor
timestamp: September 24, 2013, 09:13:04 am
content: Or they had a whole reel of extra random resistors and the BOM called for one more resistor to be placed to meet the OEM spec. Only place that would reflow would be the top of the metal can, so OHL placed them there and it met the specs

author: amyk
author_rank: Super Contributor
timestamp: September 24, 2013, 12:11:17 pm
content: That oddity has been seen before, several times...

author: andtfoot
author_rank: Unknown
timestamp: September 25, 2013, 03:45:45 pm
content: Quote from: SeanB on September 23, 2013, 05:56:01 pmIn this case it has a 12MHz marking.Didn't think to check it though. I might bust out the 'scope if I can find where I chucked the adapter.Edit: Just checked it then. It seeeeeems to be operating at 12Mhz. Connecting both probe and ground connections seems to muck up the measurement, but I got a faint 12MHz when I only used the probe and left the ground floating.Edit #2: Doh. Just switch the probe to x10 and measure between ground and one of the crystal pins. Definitely 12Mhz.

author: andtfoot
author_rank: Unknown
timestamp: September 25, 2013, 03:58:25 pm
content: Quote from: amyk on September 18, 2013, 10:47:15 amThose voltages seem pretty low for RS-232 spec. I thought it was generally +/- 3-15V.

author: uwezi
author_rank: Unknown
timestamp: February 25, 2014, 07:25:03 pm
content: I felt it would rather fit here than opening a new thread...In the students' lab today we had a problem with Prolific PL-2303-based adapters. While running fine under Linux, MacOS and Windows 7, the adapters with Prolific PL-2303 chips would not be recognized by the drivers supplied by Prolific under Windows 8.I do not know if this is a reaction by Prolific to counterfeit chips or just the implementation of their own weird philosophy:http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=212&pcid=41QuoteIn other words, legitimate or not, pre-2012 Prolific USB-adapters will not supported by Windows 8 (or any other newer version of Windows), because Windows 8 has not been mentioned in the chip's datasheet. Thank you, Prolific.USB adapters based on Silicon Labs CP2102 appear to be understood by Windows 8 without the need of additional drivers...P.S.: No, I am not using Windows 8, but some of my students are...

author: Bored@Work
author_rank: Super Contributor
timestamp: February 25, 2014, 09:21:39 pm
content: Long ago I came to the conclusion that Prolific are just a sack of liars.When they didn't manage to provide working drivers they blamed the OEMs first. When people didn't believe this any more they blamed fake ICs - as if anyone would spend time cloning their rubbish ... So now it is "it is not in the datasheet".Their own datasheet, they could change it in a second.

author: linux-works
author_rank: Super Contributor
timestamp: February 25, 2014, 09:26:00 pm
content: ftdi chips are cloned/faked.why do you not believe in fake pl2303's?they are very common and so they are a valid target for fakes.

author: Bored@Work
author_rank: Super Contributor
timestamp: February 25, 2014, 09:47:00 pm
content: Quote from: linux-works on February 25, 2014, 09:26:00 pma) Own experience. I have a good number of PL2303-based adapter cables. Some no-name, some reputable brands. Some very old, long before Prolific talked about fakes. Every single one of them refuses to work with recent drivers under Windows 7 and XP and report error 10. Prolific claims this indicates a fake. Knowing the source and age of my cables I can't believe this.b) Prolific never managed to get their Windows driver development under control. They had all sorts of fuck-ups. Like their installer trying to replace a standard windows sys driver with some version they probably lifted from an ancient hacked Asian version of Windows, breaking the driver. Or for a long time the installer as such didn't work. And just when they had another persistent driver failure they suddenly started claiming it is about face ICs. Too much of a coincidence.c) What's the point in cloning a cheap rubbish IC that is plagued for years by driver problems? Wouldn't you clone something where you would actually benefit from working drivers from the original manufacturer?

author: linux-works
author_rank: Super Contributor
timestamp: February 25, 2014, 10:17:11 pm
content: I've been bitten by the multitude of drivers for the PL chips. hate it.but regardless of the driver mess on windows, I think linux drivers deal with all the chips. I probably have a few fakes and I know I have some real ones. when I was trying to find a cheaper alternative to the ftdi for arduino devel, I was buying different cheap PL chips from china and I don't think one of them coughed when doing i/o to the arduino when using linux. on windows, I'd have to change drivers but I rarely did devel using windows as the os platform.and so, if you were using linux, you'd see that all the chips are working and if you were a company that could and does make fakes, you might consider getting in on some of this action. the PL chips are not expensive but who knows what it takes to be 'worth it' to the scammers.caps, resistors, 3 term voltage regs, chip-amp chips, pga attenuators, you name it, its being faked. its a sorry state of things.

author: uwezi
author_rank: Unknown
timestamp: February 25, 2014, 10:23:29 pm
content: Quote from: linux-works on February 25, 2014, 09:26:00 pmWell the thing is here that Prolific officially states that they stopped support for all their pre-2012 PL-2302, whether fake or not!

author: linux-works
author_rank: Super Contributor
timestamp: February 25, 2014, 10:54:18 pm
content: if that's the case, its bad behavior for prolific. you're saying that new drivers from them make valid old chips (from them) not work? did they make the older versions of drivers unavailable?

author: uwezi
author_rank: Unknown
timestamp: February 25, 2014, 11:05:19 pm
content: To my knowledge there are no old Prolific drivers for Windows 8!The same driver package found on Prolific's homepage contains drivers for different Windows versions. Installing this pack on Windows 7 gives you working drivers for exactly the same chip, for which the Windows 8 drivers out of the very same package don't work!We are talking the same ZIP-file and the same USB adapter board, connected to two different computers.http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=225&pcid=41

author: linux-works
author_rank: Super Contributor
timestamp: February 25, 2014, 11:12:18 pm
content: windows 8?uhm, ok.....

author: uwezi
author_rank: Unknown
timestamp: February 25, 2014, 11:21:13 pm
content: Quote from: linux-works on February 25, 2014, 11:12:18 pmNot me, but my students...

author: linux-works
author_rank: Super Contributor
timestamp: February 25, 2014, 11:31:10 pm
content: ah, ok.I would not willingly use win8 for anything. I see no reason for it, and as you have seen, the driver issue is worse than win7.too bad you can't choose.at any rate, since I use the chips from linux boxes, old chip or new chip does not matter to me. I would think the linux driver would detect if there is a 'quirk' by chip-id or even by testing it for a quirk and then picking the right path in code to support that hardware flavor.if you don't have that kind of control over your drivers, I can see why this would be a problem.

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: February 25, 2014, 11:37:43 pm
content: There are some workarounds listed on technet forums.Read the whole thread for 32bit,64bit .http://social.technet.microsoft.com/Forums/en-US/3f8e22a0-52bc-431b-a901-292096b46131/prolific-comm-to-usb-driver-not-working

author: uwezi
author_rank: Unknown
timestamp: February 25, 2014, 11:43:18 pm
content: Quote from: fluxcapacitor on February 25, 2014, 11:37:43 pmSounds interesting, but it's getting late here now.My solution today was to give the Windows 8-students a USB adapter with a Silicon Labs CP2102 chip instead... And I made sure to order more of these for the next I give this course!

author: linux-works
author_rank: Super Contributor
timestamp: February 25, 2014, 11:45:11 pm
content: not sure if amazon is affordable near you, but I found some quite cheap real ftdi dongles (was using them for rs232 control of test gear/SCPI stuff).

author: brainwash
author_rank: Frequent Contributor
timestamp: February 26, 2014, 12:19:16 am
content: This finding was somehow interesting:http://hackaday.com/2014/02/19/ft232rl-real-or-fake/. But the FT232 costs a lot more than a PL2303.On-topic, I have a fake(?) serial adapter bought probably 10 years ago, same PL2303HX chip. But I haven't had to use it lately since I mostly use my BusPirate. However I needed to flash some board that needed 'variable baud rate' which the BP could not do. Basically it meant that the baud rate had to be changed in the middle of the operation from 19200 to 57600, on TTL levels. So dug up the old adapter, chipped the rubber housing away and soldered some wires directly on the pins to get the to the TTL signals. To do the job I ran the flash program under an XP virtual machine.With that said I find out that work without a VM is virtually impossible - it is portable run it anywhere, runs any OS including strange Unix distributions used for specific tasks (car diagnostics, signal analyzers) and it helps with organizing stuff.I have a VM for generic Linux stuff, one for matlab stuff, some images of my old harddrives that I can boot into with the workspace ready, XP VM for running iTunes, car diagnostics and viruses, a few of them for specific hardware (routers, maemo, android), etc. Plus backups of some of those so that they can always be reverted.Sorry for the long post, just thought to share in this wonder of technology

author: GiskardReventlov
author_rank: Frequent Contributor
timestamp: February 26, 2014, 05:59:26 pm
content: This is one of the many curses of Microsoft. It's funny that prolific are trying to obsolete their own hardware. It's better than having someone else obsolete it. But it's so stupid. Next they will have the hardware stop working after 1GB of data has passed through it, as the printer makers do after so many prints.

author: linux-works
author_rank: Super Contributor
timestamp: February 26, 2014, 06:38:33 pm
content: this is the pleasure of an open osthere were times (rarely) I went in and edited the driver source to change a flag or quirk for a device or pci card. it was nice to be able to do it, rebuild the kernel, reboot and see the device work.windows and mac - you lose, here. if 'they' didn't do it, it can't be done.

author: ebclr
author_rank: Super Contributor
timestamp: August 07, 2015, 02:03:43 am
content: Just follow the instructions on this blog , and the PL2303 will work just finehttp://leftbraintinkering.blogspot.com.br/2013/05/usb-to-serial-prolific-2303-device.html