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Keyspan USB to RS-232

Would like to know, if any one has ever used this device with the Modem control lines to operate remote equipment in connection with the sound card operations? I'm having a little problem resolving an issue that seems to be very strange. My program, which uses the serial port modem control lines to activate a remote radio for TX, along with sound services. For what ever reason, i have now 2 users that have reported and issue that needs attention. Apparently, when my software is activated for transmission of data via the sound card, i also turn on one of the modem control lines to control the users radio PTT(Push to talk) line, the USB RS232 adapter decides to chatter the control line about 6 times before it stabilizes. when turning it off, at the end of data transmission, it works fine. I do open and close the file handle to the port. Open to turn on the line in transmit mode. ( i keep it open ). Close it after i have turned off the Line.

Now, i'm wonder if any of you with experience using these converters know if, opening the port while the device is initiating is causing the problem? or, is the fact that i'm also, initiating the sound card's play services at the same time maybe causing the problem? I guess i could, keep the handle open at all time's during the use of the program if any one thinks that would cure it!.. I bought today, a Belkin USB RS232 converter. that seems to work fine but, i have users that are using the Keyspan because of it's use in Macs!

--
"I\'m never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
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Reply to
Jamie
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Any chance there is RF getting into the control lines?

John

Reply to
JM

In the applications I've tried (GPS and scanner programming), the keyspan works fine. Mine has an option for "hardware" compatibility mode. I've also used those cheap Airlink usb to 232 in the same application.

If you want a real serial port (I presume for a notebook), you need to spend real money and get a Socketcom card. It even works in DOS. Note they are very easy to damage.

Reply to
miso

Oh, a very good chance, how ever, the user claims the device works fine using 2 other known programs. so there you go, the only think i can think of maybe, is maybe the sound card is active with prompt sounds when he start's up. i don't disable the Playback option or open it until i get ready to actually use it. i suppose if, the device may have a single pulse on the line when being initiated. i'll have to ask him to try it with the radio set to 0 power output. Thanks.

--
"I\'m never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5
Reply to
Jamie

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