oldest usb to serial chip/when will the patent expire - Page 1
Forum section: electronics / general

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 06:06:40 pm
content: does anybody know when the first usb to serial chip was released? when will the patents expire. maybe when the first chip is patent free we will not have to deaal with ftdi/prolific anticounterfeit drivers.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 08:55:38 pm
content: There is no patent on USB to serial converters, what are you talking about?And FTDI is free to mess up their drivers until the end of times, there is no time limit on that.There are plenty of genuine parts, but it makes sense to fake a well known brand.

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 09:28:32 pm
content: ftdi's die implementation is patented. any one can make a usb to serial chips, but they can not legally make clones of ftdi chips. if clones can be made legally then ftdi's chip implementation would become a de facto industry standard. ti , microchip , ONsemi, nxp could then make ft230X clones. like 555 timers ,74 series logic, etc.

author: donmr
author_rank: Regular Contributor
timestamp: June 07, 2016, 09:34:10 pm
content: A chip implementation can have a copyright and/or a maskworks but not a patent. Patents are on a process and chip might use a patented process (dabatable) but the chip itself won't be patented.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 09:34:17 pm
content: Quote from: peterthenovice on June 07, 2016, 09:28:32 pmNo one is cloning the die. It is a pointless exercise. FTDI chips are MCUs with USB firmware. All clones are re-implementing the firmware on different MCUs.And all those clones of 555 are not actual clones, they use different masks. They are just second source supplier. FTDI does not need second source suppliers.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 09:39:48 pm
content: Quote from: peterthenovice on June 07, 2016, 09:37:14 pmBut why would they? They are free to implement their own thing. And why would FTDI not try to resist this?There is always going to be differences, so FTDI will just make a new firmware update that will kill all the clones again.You can freely create USB to serial adapters, just use your own VID/PID and write your own drivers.You don't even need drivers. All OSes support standard USB ACM. I use it all the time with my own designs and it works perfectly. On Linux it just works out of the box. On Windows you need an INF file, but no actual drivers required, they are a part of the OS already.

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 09:41:57 pm
content: usb flash drives use a mass storage driver. usb to serial devices could use a cdc driver that works across devices.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 09:43:19 pm
content: Quote from: peterthenovice on June 07, 2016, 09:41:57 pmThey already can. Why none of the manufacturers implement CDC ACM and prefer their own proprietary solution - ask those manufacturers.

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 09:47:00 pm
content: why do they not implement a cdc acm complatible device? i think the Microchip MCP2200 is cdc acm.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 09:49:55 pm
content: Quote from: peterthenovice on June 07, 2016, 09:47:00 pmI don't know.Quote from: peterthenovice on June 07, 2016, 09:47:00 pmI may be wrong, but I think some Cypress IC implemented it. But I can't verify it right away, their site does not seem to mention it.I've only seen ACM used in software implementations. For example, Atmel EDBG debugger IC uses CDC ACM for USB to UART translation.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 09:55:13 pm
content: On further search, here is the quote from Cypress employee herehttp://www.cypress.com/forum/usb-full-speed-peripherals/cy7c64225-linux-devttyusb-supportQuoteSo here you go, one sane manufacturer out there.

author: Monkeh
author_rank: Super Contributor
timestamp: June 07, 2016, 09:55:28 pm
content: Both Cypress and Silicon Labs make CDC ACM driven chips.E: At least I think Silabs do. That may be my brain misfiring.

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 09:55:52 pm
content: on cyress's site for there usb to serial in the driver section if ound this.http://www.cypress.com/products/usb-serial-bridge-controllerCypress provides free USB CDC and USB Vendor Class drivers for USB-Serial Bridge Controllers.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 09:58:02 pm
content: Quote from: Monkeh on June 07, 2016, 09:55:28 pmPart numbers? CP210x use proprietary protocol.

author: Monkeh
author_rank: Super Contributor
timestamp: June 07, 2016, 10:00:33 pm
content: Quote from: ataradov on June 07, 2016, 09:58:02 pmI may be mistaken. I'm sure I recall one of their chips operating under CDC ACM or a proprietary extension, but it may have been from another manufacturer.It may have been one of the Cypress chips and I've got my wires crossed.

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 10:03:06 pm
content: https://www.silabs.com/Support%20Documents/TechnicalDocs/cp2104.pdfit says in their datasheet that there drivers are royalty-free not cdc acm.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 10:04:26 pm
content: Quote from: peterthenovice on June 07, 2016, 10:03:06 pmIf it is real CDC ACM, then you don't need any drivers at all. It is possible that all their "drivers" are doing is just a simple install of INF files.

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 10:06:46 pm
content: http://www.microchip.com/wwwproducts/en/MCP2200microchip supports cdc

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 10:09:47 pm
content: Quote from: peterthenovice on June 07, 2016, 10:06:46 pmYep, one more to the list.Now the challenge would be to find cheap Chinese IC with CDC ACM

author: Monkeh
author_rank: Super Contributor
timestamp: June 07, 2016, 10:10:51 pm
content: I distinctly recall a chip which supported both CDC ACM and an extension thereof, but I can't seem to find any reference to it now.. Just ignore me until my marbles roll back.Quote from: ataradov on June 07, 2016, 10:09:47 pmAnd then the challenge will be to get it working right!

author: peterthenovice
author_rank: Regular Contributor
timestamp: June 07, 2016, 10:15:30 pm
content: ch340 is the cheapest i think. but no cdc acm and bad mac os x support

author: nctnico
author_rank: Super Contributor
timestamp: June 07, 2016, 11:44:20 pm
content: Quote from: ataradov on June 07, 2016, 09:43:19 pmThe problem is that whoever made the CDC specification totally forgot about plain serial ports! The CDC ACM devices identify themselves as a modem to the computer. This is why Linux doesn't enumerate CDC ACM devices as ttyUSBx but ttyACMx.

author: ataradov
author_rank: Super Contributor
timestamp: June 07, 2016, 11:50:18 pm
content: Quote from: nctnico on June 07, 2016, 11:44:20 pmWhat difference does it make how they identify themselves? They work as COM ports just fine.

author: oPossum
author_rank: Super Contributor
timestamp: June 08, 2016, 01:26:36 am
content: Quote from: Monkeh on June 07, 2016, 10:10:51 pmProlific PL2303 is CDC ACM with extensions to support all the handshake lines.This can be verified by looking at the Linux drives for both.

author: oPossum
author_rank: Super Contributor
timestamp: June 08, 2016, 01:30:33 am
content: It is also mentioned in the PL2303 data sheet.Quote from: Prolific