PaulS:
Yes.Why such a slow baud rate?
Why do you need to copy data from one SD card to another that way?
I need to make it work at all, first, then I can boost speed to whatever will give me error-free copies.
The sending sd is on a teensy powered datalogger buried within an airframe where it isn't easy to get at between flights. the idea was to plug a nano powered box into a port on the outside of the plane and order the teensy to send the file to the nano-box.
if the softwareserial is where I'm having the trouble I'll use another teensy 3.2. to get another serial port.
My experience has been that I never make a single mistake with these things, almost always both hardware and software, but I'm patient and can usually substitute simple routines and other hardware and utlimately make something work, but the 15% comprehension can really slow me down.
Edit 3/1/16 OOPS: that should be that i seldom make a single mistake, usually it's several.