Anyone been able to get SoftwareSerial or Alt Serial to work on Yun?

I can't seem to get either to function. I see some garbage coming out depending on what pins I use. Can anyone confirm it works?

Maybe you are using the wong pins

From the refernce page:

Not all pins on the Leonardo support change interrupts, so only the following can be used for RX: 8, 9, 10, 11, 14 (MISO), 15 (SCK), 16 (MOSI).

http://arduino.cc/de/Reference/SoftwareSerial

I haven't even gotten to the point of worrying about the receive yet. I'm simply trying to print a string out of a sketch to a com port on my laptop. Nothing but gibberish.

I just did a test, I must admit I haven't tried using softwareserial on the Yun, but it worked as expected, no problems.

my test sketch below.
I used a USB/serial converter connected to pin 9 on the Yun

#include <SoftwareSerial.h>

SoftwareSerial mySerial(8, 9);
int x = 0;

void setup()
{
  mySerial.begin(9600);
  mySerial.println("Hello, world?");
}

void loop() // run over and over
{

  mySerial.print("Loop");
  mySerial.println(x);
  x++;
  delay(1000);
}

Thanks ERNI for taking the time to verify. Much appreciated. Something still isn't right though. With your sketch I still get odd characters. I'm using a serial card slot adapter on my laptop which I use all the time for various things with no problem. I even connect pin 8 to 9 and then sent the mySerial.read() out my Serial1 port and monitored that. Same result. I get in ASCII "u w U ENQ". Does the Arduino output standard RS-232 levels? Don't think pinmode matters? Doesn't seem to make any difference. Here's my code...

#include <SoftwareSerial.h>

SoftwareSerial mySerial(8, 9);

void setup()
{
    pinMode(8, OUTPUT);
    pinMode(9, OUTPUT);
    mySerial.begin(9600);
    Serial1.begin(9600); // Set the baud.

  
   // Wait for U-boot to finish startup.  Consume all bytes until we are done.
  do {
     while (Serial1.available() > 0) {
        Serial1.read();
        }
    
    delay(1000);
  } while (Serial1.available()>0);
  Serial1.print("Serial Ready");
}

void loop() // run over and over
{
  mySerial.print("TEST");
  Serial1.write(mySerial.read());
 

  delay(1000);
}

Does the Arduino output standard RS-232 levels?

No that would mean -13 to +13V, so if that is what you are using, it will damage your Yun.
Arduino use TTL level (0.5V).
One more thing standard RS-232 are inverted, which could explain why see garbled text.
https://www.sparkfun.com/tutorials/215

I use one of these cheap USB/Serial converters.

http://www.ebay.com/itm/New-Upgrade-PL2303HX-USB-Serial-To-RS232-TTL-Chip-Auto-Converter-Adapter-Module-/290984791202?pt=UK_Computing_CablesConnectors_RL&hash=item43c00b8ca2

If you have an Arduino Uno you could use that instead

Ah ha. My ignorance exposed. That explains a lot. So your serial to usb automatically adjusts to the TTL levels? Thanks!