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marek Tl Posts: 3 United Kingdom	Posted - 4/22/2004 1:35:40 AM I am using a piece of software that takes data in to the serial port. The data is from a GPS receiver (NMEA data) I want to put a modem between the GPS receiver and the PC so that the GPS data comes from a remote site. The GPS software does not support modem dial-up so I am trying to fool it into thinking the data from the modem is the GPS receiver. I have written a small piece of code using AT commands to dial the remote GPS receiver but when the connection is established and the software releases the serial port, the modem hangs up. Is there any way I cn get the modem only to disconnect on an ATH command rather than when windows closes the reference to the serial port? Many thanks
v.Richard Tl Posts: 6222 USA	Posted - 4/23/2004 9:12:57 AM If you use an external serial modem, you could connect the modem to PC via a breakout box (or specially wired cable) and prevent modem from disconnecting when port is closed. It may be possible with internal modem if the internal is a full hardware-controller-based modem that supports commands to disable hangup on drop of DTR. Aloha! Richard.
marek Tl Posts: 3 United Kingdom	Posted - 4/27/2004 6:02:06 AM Do you know which line to break into for this? Does the line to the modem then need pulling high or low? Thanks
v.Richard Tl Posts: 6222 USA	Posted - 4/30/2004 2:08:42 PM Breakout box - Supply the modem with high voltage (+5V) on the DTR line by breaking it out from the PC - a breakout box would let you isolate DTR from the PC, and jump a line that is always high from the modem side (like DSR) to DTR. Aloha! Richard.

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