PCI to RS232 converter? - Page 1
Forum section: electronics / projects

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 05, 2016, 04:35:45 am
content: Is there any such thing as a PCI to RS232 or TTL converter?What I mean is that I would like a module which I can plug a PCI card to, and it will output RS232 signals out to a uC (or TTL for that matter).I have a few PCI cards that are 'plug and play' and once plugged in the PC sees it as a serial COM port.I could only find PCI cards that have a RS232 jack to connect peripherals to, not the other way round.Thanks in advance!EDIT: I have attached what I intend to use it for.

author: helius
author_rank: Super Contributor
timestamp: February 05, 2016, 04:56:56 am
content: I'm struggling with what you would expect this thing to do.How about a motherboard with a PCI slot, and a USB serial adapter?

author: casinada
author_rank: Frequent Contributor
timestamp: February 05, 2016, 05:24:26 am
content: http://www.amazon.com/StarTech-com-RS232-Serial-Adapter-PCI1S550/dp/B00006B8C5There are many like that with serial (RS-232) and also Parallel ports.For newer computers with PCI-Xhttp://www.amazon.com/Crest-Serial-Profile-Brackets-SI-PEX15037/dp/B00B5L9P36/ref=sr_1_1?ie=UTF8&qid=1454649811&sr=8-1&keywords=pci+express+serial+port+card

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 05, 2016, 05:32:10 am
content: Quote from: helius on February 05, 2016, 04:56:56 amI have this module (of my client's) which plugs into a PC's PCI port and outputs a stream of data via a COM Port, and I would like to have that stream of data send directly to a uC (eg Arduino) instead as it will consume much less power and be more reliable (ie less maintenance, and no attending required). Currently, the PC's sole job is to receive the data which is overkill and consumes a lot of electricity. Connecting to a PC and outputting the RS232 data to my uC defeats the purpose.

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 05, 2016, 05:36:11 am
content: Quote from: casinada on February 05, 2016, 05:24:26 amSorry mate, that's not what I need... I need the direct opposite of that card. Ie: Plug in a PCI Card, and the other end outputting RS232 data without a computer.

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 05, 2016, 05:46:00 am
content: Quote from: helius on February 05, 2016, 04:56:56 amI just uploaded a BFD showing what I intend to use it for..

author: helius
author_rank: Super Contributor
timestamp: February 05, 2016, 06:03:20 am
content: There are no actual COM ports on the PCI interface. It sounds like the PC runs a driver that emulates a COM interface and sends the data to a port in the PCI device. This must be specialized to the specific PCI device and the application that uses it, so a generic adapter would not work at all.You can get PCs that use 5 watts or less, look for Mini-ITX or Geode SBCs.

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 05, 2016, 06:12:37 am
content: Quote from: helius on February 05, 2016, 06:03:20 amUnfortunately that doesn't remove the 'fustration' layer... It's currently impossible to run the PC completely unattended without spending additional thousands just to automate everything. Even after automating all the hardware portions, Windows is still another resisting factor.How about a raspberry pi? It's not what I would need, but its a step..

author: nctnico
author_rank: Super Contributor
timestamp: February 05, 2016, 12:37:03 pm
content: I'd look for an embedded Linux board with PCI express and add a PCI expres to PCI bridge to use the PCI card. Using Linux has the advantage of sorting out a whole pile of potential problems with network security and performance.Edit: If you know how to control the PCI card on a driver/hardware level you could also use some standard logic (a small CPLD would be ideal) to make a low frequency PCI bus which talks to your Arduino using I2C or SPI. AFAIK there is no specification for the minimum frequency on a PCI bus.

author: Pack34
author_rank: Frequent Contributor
timestamp: February 05, 2016, 07:55:20 pm
content: Is the PCI card accomplishing some proprietary function? Is it necessary?

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 06, 2016, 01:00:00 am
content: Quote from: Pack34 on February 05, 2016, 07:55:20 pmUnfortunately, yes... It's accomplishing a proprietary function. My client has 3-5 of these lying around.It's the 'last-gen' version of another module (the latest gen one has RS232 out, and I'm having problems with that as well) but it'd be a really big waste to just chuck them aside.It's also really wasteful right now to run whole PCs because of their heavy electricity bills.It's also very difficult to sell to my client the SBC idea because right now the PCs have a plethora of issues that prevent full autonomous running (and I know this because I developed the Win32 software for him).

author: uncle_bob
author_rank: Unknown
timestamp: February 06, 2016, 01:19:18 am
content: HiSimple answer = no, PCI is a pretty complex and high speed interface. RS-232 is not up to the task of running PCI. Your only off the shelf option is some sort of singe board computer with a PCI slot on it. If you are up to spinning your own board, you can implement PCI on a number of FPGA's. Often it's a licensed product though. That would let you talk to the board and set up a custom state machine that did whatever it is the poor board needs done. After digging into a few drivers, that could be a couple thousand lines of code or it could be a lot more than that.One thing that is missing from your drawing. The board (I assume) runs in a PC right now. That PC interacts with the board to do more than supply power. Part of the above assumes that it is not just a simple way to get power to the board.Bob

author: nctnico
author_rank: Super Contributor
timestamp: February 06, 2016, 02:03:28 am
content: Quote from: thejoggingmat on February 06, 2016, 01:00:00 amIt may help to get someone involved in the project who can setup a Linux board and have that run standalone. Running Linux from a read-only partition on an SD card is a rock solid solution. OTOH you are going through a lot of trouble to try and save 5 (obsolete?) PCI cards. Isn't it an option to come up with a solution which replaces the PCI cards all together? That way you have full control over everything so the customer isn't confronted with so many bugs.

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 06, 2016, 02:30:03 am
content: Quote from: nctnico on February 06, 2016, 02:03:28 amThat's (solution that replaces the PCI cards altogether) what my client and I are seriously considering as well. The PCI card decodes proprietary signals coming in from POTS and outputs streams of plaintext data via the 'virtual' COM Port (or via RS232, for the latest gen card). There are ASICs on the cards just to decode the data. The only way for me to completely gain full control over everything is to get all his clients to change their end-user panels which is impractical. Basically my client has been running a small business, installing and setting up home/office security/alarm monitoring for decades and the proprietary signals are for remotely monitoring the end-user panels: Seeing who accessed whichever panels, or which alarms were triggered and having the monitoring data sent realtime to his clients. I've been upgrading his software part of things, now I just began to move on to the antiquated hardware.The PCI cards have been running solidly and continuously for >10 years, have seen tons of motherboards come and go over the years and still have a lot of life left in them. I cannot say the same for their latest generation crap though.The monopoly dealing in these 'technology' of home/office security systems and access controls are lagging behind significantly. For instance, their latest generation card are still supporting MSDOS and not anything after Windows 7 (and only Win98 for the last gen PCI cards).

author: uncle_bob
author_rank: Unknown
timestamp: February 06, 2016, 02:40:05 am
content: Quote from: thejoggingmat on February 06, 2016, 02:30:03 amHiOk, that's a lot more than minimal interface between the computer and the card. There is no way you will be able to do that with just a PCI interface on an FPGA. You need a full cpu running an OS that supports the cards.Bob

author: thejoggingmat
author_rank: Regular Contributor
timestamp: February 06, 2016, 02:41:04 am
content: Quote from: uncle_bob on February 06, 2016, 02:40:05 amYep, I guessed as much. I'll just have to see what my client wants then.