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cali yaris
11-20-2009, 12:13 AM
Are any better than others?

This is for my car, so i posted up in here. The AEM EMS management requires a serial port, which my laptop does not have.

http://tinyurl.com/yzvdk7z

supmet
11-20-2009, 01:10 AM
Not really, I'd go cheap and buy 2 or get a middle of the line one.

Do you know if your computer USB port is 2.0? If its not there's no point in spending money on a 2.0 adapter

YarisSedan
11-20-2009, 01:30 AM
Now days most is 2.0. I dont think it would matter though since your transfering something that is serial to usb. The information is slow anyways nothing that 1.0 usb would hinder. Just pick one thats cheap and looks nice

WolfWings
11-20-2009, 08:52 AM
Not all USB/Serial converters are the same!

In fact, many (if not most of them) don't work AT ALL with 'serial dongle' devices, such as Cisco Routers, and many ODB/whatever adapters and the like, because they only present a 'serial port' to the operating system, not a raw DB-9 connector.

I.E. They prevent low-level fiddling with the pins on the socket, which the old physical serial and parallel ports allowed, a reason people made SNES/NES/Genesis/whatever controller-adapters that used those ports.

This is doubly true if you try to find a Bluetooth->Serial adapter, and a LOT of the bluetooth ODB-II adapters are actually such a high-end Bluetooth->Serial adapter (often an STM4100) direct-wired to any one of a multitude of Serial->ODB-II adapters.

Expect to pay about $40-60 for one of the higher-end 'everything works' USB adapters, and you'll be fine, but avoid the $10-30 stuff if you can.

Tamago
11-20-2009, 09:59 AM
garm, i bought one from radio shack. no longer need it, if you want, let me know. it worked with my MAFtranslatorPro

CTScott
11-20-2009, 10:05 AM
I do a lot of RS232 serial comm with legacy devices (Allen Bradley PLCs, Industrial Embedded 386 PCs with an RS232 terminal interface for screen and keyboard, our own custom PIC, 68HC11, and 68000 based devices, etc.)

Now that 99% of laptops don't have serial ports, I end up using many USB to RS232 adapters. I have not found any yet that haven't actually worked for me. Almost all of them use the exact same chipset. My personal favorite is the Bytecc, because it is only $9.


http://www.newegg.com/Product/Product.aspx?Item=N82E16812101118&cm_re=usb_serial_adapter-_-12-101-118-_-Product

cali yaris
11-20-2009, 10:20 AM
Thanks guys. The one I bought from Fry's didn't work (USB to serial on one side/parallel on the other), I should have put that in the first post.

I'll take a pic of it. Tamago, if you have a spare to try, that would be great.

CTScott
11-20-2009, 10:27 AM
Thanks guys. The one I bought from Fry's didn't work (USB to serial on one side/parallel on the other), I should have put that in the first post.

I'll take a pic of it. Tamago, if you have a spare to try, that would be great.

The key is to look in "device manager" under system, hardware in control panel. Under ports (com and lpt), you should see the device listed with a serial port number (com1, com2, com8, etc.). Sometimes the SW is only setup to address com1-com4 (and the USB ones tend to automatically jump in at com8 or higher).

If that's the issue with the app you're trying to run, you can force the USB one to be a lower com port. Under properties for the device (in device manager), in the port setting tab, click on advanced and then port number, and change it to a lower one.

Tamago
11-20-2009, 12:23 PM
The key is to look in "device manager" under system, hardware in control panel. Under ports (com and lpt), you should see the device listed with a serial port number (com1, com2, com8, etc.). Sometimes the SW is only setup to address com1-com4 (and the USB ones tend to automatically jump in at com8 or higher).

If that's the issue with the app you're trying to run, you can force the USB one to be a lower com port. Under properties for the device (in device manager), in the port setting tab, click on advanced and then port number, and change it to a lower one.

garm, try this first :)

RedStickHam
11-24-2009, 01:59 PM
What I've found with USB to Serial adapters is they are flakey to say the least. I've tried a few of them with my laptop for ham radio applications, and they have been problematic to put it mildly.

I haven't tried them with my GPS yet, since my aging 1.583ghz desktop still has a serial port. I'm not sure what I'm going to do for my GPS once that PC goes and has to be replaced with one that doesn't have a serial port.

RedStickHam

cali yaris
11-24-2009, 02:14 PM
Thanks guys - I'll try forcing the COM port the next time I'm with the car (it's at Art's getting some more work done at the moment).

IllusionX
11-24-2009, 11:31 PM
Just as CTScott says.. just about any RS232 to USB work. I would tend to go with the cheapest ones i can find....

jonydepp
12-10-2009, 02:44 AM
Hi,

I am Jony.This is my first visit to site.I am new to this site,but I’ve enjoyed posting in your forums.i bought one from radio shack.no longer need it,if you want,let me know.it worked with my MAFtranslatorPro.Thank you very much and Stay connected with me.

dean_park
12-11-2009, 01:01 AM
I don't know much about talking to the device you are looking at, but it's true that not all USB to serial devices are the same. I have a sea-level brand that I use to talk to control boards for various HVAC and building automation products. It's the only brand I've found to have a good consistent handshake with the products I communicate with. Others are OK with one way comm, but usually lose a few packets (which conviently hose the firmware on the machine and I have to start over).