softwareSerial issue


Could someone comment on this one. I have Duemilanove board, GPS receiver connected to serial pins 0 and 1, RF transmitter APC220 connected to pins 10, 11 setup with softwareserial library. This is a scenario:
step 1: board reads NMEA data from GPS receiver (baud 57600)
step 2: board waits, five seconds delay(5000) - this step is introduced for troubleshooting
step 3: something is sent to RF module (baud 1200), can be one constant byte.

The problem is that third step actually does not happen (or happens but roughly every 10 iterations) unless I do disconnect physically GPS receiver in between step 1 and 3. Step two is there to give me a time to disconnect GPS communication line. Why is it happening ? Is there any cure for it ?
Thanks for any help or comments.


The problem is that third step actually does not happen

Why not? If you want us to look at your code, you need to clean your screen.

ok, I will come back with code and better description.

board waits, five seconds delay(5000)

So, does your GPS send five seconds worth of NMEA?
Maybe your serial input buffer is overflowing.

But, as PaulS rightly states, without seeing code, we're all just guessing.

5 sec is only there to give me opportunity to disconnect GPS before step 3 is executed. Anyways I have lowered baud rate to 9600 and reprogrammed GPS to send minimum data required for me, it works now. I will come back at some stage with code to understand what is happening there, at the end I want to work on default GPS settings. Thanks for your help because it actually helped.


softwareserial library is depreciated,

use NewSoftwareSerial instead => google is your friend