[majoconz]

I have a Navman 1220A marine GPS antenna/receiver that outputs RS232 NMEA183 that is very picky on how you start it up. It wants the 5volt power applied first but without the COM port connected. My receiver COM port goes via a COM to USB adapter which probably has a MAX233 inside of it. Once the receiver has had a few minutes, then I can plug the adapter into another USB port and it works a treat. It doesn't matter whether it goes into cold or warm start, it's always the same. If I don't wait long enough, it takes charge of the mouse which then zooms all over the screen with occasional button presses!