Rs232 to usb

[kinarfi]

I have on old Magellan MAP330 GPS that has an RS232 output that I want to use with an RS232 to USB converter I have. The GPS output is only 3 wires out to the DB connector,
1 = Data in (pin 3 on DB-9) yellow wire.
2 = Regulated 3.86vdc, red wire.
3 = Ground (pin 5 on DB-9) and ground on cigarette-lighter plug, black wire.
4 = Data out (pin 2 on DB-9) orange wire.
I appears to be connected correctly, the port and baud rate match, but the rx & tx lights on the converter never light up.
any ideas or suggestions?
Thanks,
Kinarfi

 

[RCinFLA]

You have no flow control on the GPS output. You may need to tie the CTS and RTS together on the converter box. There is also possible DTS and DSR liines that have to be tied together.

Other item is to be sure they are true RS232 physical or 3 or 5 v logic. The physical RS232 interface inverts the raw data and level shifts it to bipolar going at least -3v to +3v to max of -12v to +12v.

 

[kinarfi]

Thank you RCinFLA, Is there any reason NOT to tie DTS to DSR?
The adapter I have is this one, https://www.usbgear.com/USBG-232MINI.html
since the GPS I'm using is a Magellan MAP330 and will run off of 5v USB power, I opened the converter and jumpered the 5 volts from the USB input to pin 1, so pin 1 is power for GPS, pin 2 is data out, pin 3 is data in, pin 4 is tied to pin 6, pin 5 is ground, and pin 7 is tied to pin 8, pin 9 is empty. I did open the trace to pin 1, DCD.
My intent is to permanently mount this under a plastic vent in my Motor home with a lead to the cab so I can have a good signal to my lap top which will be running on the floor, the signal received from a unit on the dash gets real iffy, especially in narrow canyons.
Thanks again for your help,
Kinarfi

 

[Mr RB]

It's most likely to be logic-level serial data, and opposite data polarity to RS232.

If connecting to USB you probably need a USB->TTL serial converter. They work fine with 3.3v logic level signals.

 

[koolguy]

I have on old Magellan MAP330 GPS that has an RS232 output that I want to use with an RS232 to USB converter I have. The GPS output is only 3 wires out to the DB connector,
1 = Data in (pin 3 on DB-9) yellow wire.
2 = Regulated 3.86vdc, red wire.
3 = Ground (pin 5 on DB-9) and ground on cigarette-lighter plug, black wire.
4 = Data out (pin 2 on DB-9) orange wire.
I appears to be connected correctly, the port and baud rate match, but the rx & tx lights on the converter never light up.
any ideas or suggestions?
Thanks,

Kinarfi

i have done this you can check my thread.

 

[kinarfi]

i have done this you can check my thread.

More information, Please

 

[kinarfi]

contacted manufacturer and they said:
"Three wire serial usually implies RX/TX/GD connections, which are pins 2, 3, & 5 on our adapters:
https://en.wikipedia.org/wiki/Serial_port_pinouts
The remaining pins can "hang" free."

Then I asked if there was a way to test my converter and they said:
"Jump pins 2-3 together, open a terminal program (Putty or Hyperterminal) and type something into the console. If the adapter is working correctly, (and youve jumped the correct pins) you should see whatever you type.
This is known as a "loopback test"
Maybe this will help other who have RS232 to USB adapters