Using Uni-T UT61E with PCI R232 card. - Page 1
Forum section: electronics / testgear

author: Creep
author_rank: Regular Contributor
timestamp: May 18, 2014, 05:56:33 pm
content: I was wondering if anybody could tell me if the Uni-T UT61E PC interface works with PCI R232 cards. I've heard a lot about USB adapters failing to deliver in these terms. Is it the same situation with PCI cards or do those work properly with the meter?Looked around the forums a bit, but coldn't quite find the answer here. I apologize if it has been discussed before.Thanks.

author: Towger
author_rank: Super Contributor
timestamp: May 18, 2014, 06:11:19 pm
content: There 'should be' no problems with a proper rs232 card. It wad not that long ago that they came as standard in most PCs. Most of the problems with the USB ones are due to the number of cheap clones on the market and that the OEM have updated their drivers to stop them working with the clones.

author: Creep
author_rank: Regular Contributor
timestamp: May 18, 2014, 06:57:53 pm
content: Ok, thanks for the info. Off to order a PCI RS232 card, i guess.

author: Monkeh
author_rank: Super Contributor
timestamp: May 18, 2014, 07:02:33 pm
content: A PCI card will cost you as much as building a working adapter, and not come with any learning experience.

author: Rick Law
author_rank: Super Contributor
timestamp: May 19, 2014, 01:08:50 am
content: Quote from: Creep on May 18, 2014, 05:56:33 pmThe UT61e's RS232 hardware itself is NOT the picky one. It is their UT61e stock software that is picky.After a lot (lot lot) of experiments with both hardware and software, I believe the issue is just parity. The UT61e stock software only opens the port in19200,8,e,119200,7,1,E which some chipsets supports readily (such as FT chipset) but some doesn't. I wasunableto get the UT61e software to work with my Targus (Phillips chipset) RS232-USB. It doesn't support parity at that speed.Onceafter I narrowed the problem to parity, now myTargus RS232-USB works just fine with the UT61e using my own Java based direct-to-disk logger(by not using parity). To confirm the issue, I did more experimentation: I was able to even have the Arduino UNO's RXTX (pin0 and pin1) pick up the UT61e's reading using a bare Max232 chip as voltage level translation.So, if yourPCI RS232 port supports parity at 19200(as my motherboard RS232 ports do), you will have no problem. If you are set on PCI cards, just hunt for RS232 adaptors that support parity, or get the RS232-USB using FT chipset... or if you plan to roll-your-own (like a simple QBasic program), the UT61e's RS232 is very easy to work with.(Just don't use parity)I now use exclusively my home-made JAVA based logger - not a very polished program but I need to do direct-to-disk (and min/max/average) which the UT61e software doesn't do.RickEDIT: corrected a typo. The 61e is locked to 19200,7,1,E, (7 bits, not 8... funny how the brain works. When I got up, not even thinking about this at all, but it suddenly occurred to me I made a mistake last night when I post.)

author: sportq
author_rank: Regular Contributor
timestamp: May 19, 2014, 07:47:32 am
content: I've used my UT61E with a Perle PCI dual serial card. I have several for sale if you're interested. Note, it's PCI, not PCIe.Pete

author: mariush
author_rank: Super Contributor
timestamp: May 19, 2014, 08:08:08 am
content: I'm using a cheap serial to usb adapter from eBay, it cost me maybe 4$... the seller was this company:http://stores.ebay.com/safekom/They have a bunch of cables or adapters here starting from 4.5$ today :http://stores.ebay.com/SAFEKOM/RS232-Serial-DB9-Cables-/_i.html?_fsub=4272159017&_sid=647198087&_trksid=p4634.c0.m322Worth trying one before throwing tens of dollars on pci cards.

author: Rick Law
author_rank: Super Contributor
timestamp: May 19, 2014, 04:30:54 pm
content: Quote from: mariush on May 19, 2014, 08:08:08 amI would definitely agree that PCI is not worth the trouble if you are running Windows or with good driver support. But, if you are running DOS, Linux, or PE, the PCI serial is a good alternative if the motherboard doesn't support RS232 and the driver is having hiccups for your OS.An open-port, read, write-file program is not hard. I made a (Server2003 based) Bart-PE environment that runs my Java version of UT61e logger. I can use either of my old laptop or even my old server with real RS232 -- all without worry about driver loading or program loading. The DOS version (in theory - not tried) should run with my old-old-old 64k ram machine.

author: magiccow
author_rank: Contributor
timestamp: June 13, 2014, 05:37:06 pm
content: Quote from: mariush on May 19, 2014, 08:08:08 amSame for me. I found I had to enable hardware flow control in the control panel for the port. I am guessing that the electronics in the USB cable are taking power from DTR or RTS lines, so this must be raised by the PC.The UNI-T software seems like a nice basic logger. I like the way you can set upper/lower limits and a big red/green panel shows whether you're inside the window to not.Tricks to make the UNI-T software work:Make sure your USB cable is configured (in control panel/port/port settings/advanced) to COM1 to COM4, which are the only options available on the loggerI had to unplug my Bluetooth dongle, as the logger software tried to interact with it and crashed.Don't forget to disable any other application using the same COM port

author: magiccow
author_rank: Contributor
timestamp: June 13, 2014, 05:39:41 pm
content: Quote from: Rick Law on May 19, 2014, 01:08:50 am

author: Creep
author_rank: Regular Contributor
timestamp: June 19, 2014, 02:23:39 pm
content: Just wanted to confirm this as working:http://www.aliexpress.com/item/Cheap-New-USB-to-RS232-COM-Port-Serial-9-Pin-DB9-Cable-Adapter-Converter-Dropshipping-111/1610360731.htmlTried it with the meter today, after changing the COM port, it works like a charm.So in case somebody want's to go for the UNI-T USB cable, then this is a super cheap working alternative.

author: aroby
author_rank: Regular Contributor
timestamp: June 19, 2014, 02:50:31 pm
content: Wouldn't it be cheaper and less hassle just to buy the USB cable for the meter? Franky sells them.Anthony

author: Creep
author_rank: Regular Contributor
timestamp: June 19, 2014, 03:02:10 pm
content: Less hassle: yes.Cheaper: definitely no. As posted above, the total costs for the adapter is 2.65$ shipped. Considering windows finds the driver automatically and just by changing the com port, it simply works, I don't see a problem with this solution. Franky sells the USB cable for around 16 bucks so you do the math.

author: ve7xen
author_rank: Super Contributor
timestamp: June 20, 2014, 06:34:08 am
content: Quote from: Rick Law on May 19, 2014, 04:30:54 pmI would say the exact opposite, at least in the Linux case. Every USB->RS232 dongle I've ever tried (and as a network admin, I use them a lot...) has "just worked" in Linux. No annoying find-the-right-driver installs (drivers for all common chips are included in the kernel), no blue-screen-of-death due to angry OEM locking out clones (hi Prolific), no OS upgrade "oops there's no driver" problems, just plug it in and /dev/ttyUSB0 appears and works flawlessly.On Windows the only reliable way seems to be 1) buy a lot of different adapters until you find one that works well (this is what we've had to do at work) 1a) build your own based on FT chipsets that seem to work fine or 2) use an old-school PCI 16550-based UART.

author: Rick Law
author_rank: Super Contributor
timestamp: June 20, 2014, 04:19:19 pm
content: Quote from: ve7xen on June 20, 2014, 06:34:08 amve7xen, a typo was making it easily misread... I said the same thing you just did but with a typo..."...the PCI serial is a good alternative if the motherboard doesn't support RS232andorthe driver is having hiccups for your OS"

author: lrai
author_rank: Newbie
timestamp: November 19, 2015, 09:44:47 am
content: Hi, I have a problem with my UT61E and R232. On my home computer (win7) works ok. Same cable on different computer (winxp) does not work. I have tracked down the problem to RTS / DTR levels. When the Uni-t interface application initialize the com port something weird happens on winxp and the RTS / DTR logic levels are reversed RTS is high and DTR is low. When the port is not initialized both RTS and DTR are low.

author: lrai
author_rank: Newbie
timestamp: November 19, 2015, 10:58:30 am
content: Update .... Problem solved, it was the serial header cable. Despite being keyed they were not compatible. I have tested 2 of them and was confident that they were ok because they only fitted one way. Luckily i've used windmill com debug to toggle RTS/DTR individually and figured that they were swapped. Then i've used a third header cable, this time one with the missing pin key type and problem solved.Lesson of the day ... trust no serial header cable ... with or without key.

author: Deathwish
author_rank: Unknown
timestamp: November 19, 2015, 11:08:56 am
content: I have always hated that they did away with the serial and parallel ports on mobos, so much stuff still use them.