In my particular GPS the PPS signal has been converted to RS232 logic/voltage levels: logical low - +5V, logical high -5V. This means that most of the 1 second period the line is at +5V (logical 0), then goes to -5V (logical 1) for about 50ms (that's the pulse).
I connected this line to RS232 CD line (pin 1 on DB9 connector). Will this work or do I need to use an RS232 to TTL converter?
According to "gpspope -r" gpsd sees PPS signals but I am worried that it looks at rising edge which is 50ms after beginning of the pulse.
Thank you.