I tired to execute this program in picoC
 
printf("Hello world\n");
 
it loaded successfuly via XMODEM and i was able to verify the contents of the flasbuffer using 'zd'
however when i type in 'Q' it does not print "Hello world"
i also tried writing it into flash memory 'zw' and then type 'Q' but it immediately goes to
 
starting picoc
 
help please! i'm a beginner that has been looking at searching a lot the forums for a while now.

I've written code to run my SRV1 camera from my iPhone (http://www.youtube.com/watch?v=s8w76_7unBs&feature=mfu_in_order&list=UL) and from Python, using the standard ASCII protocol (http://www.surveyor.com/SRV_protocol.html).  Now I would like to add some code to interact with other digital devices, via the GPIO pins -- e.g., press a button in my iPhone app to assert a value on a given GPIO pin.  It appears that in order to do this I must use Pico C.  So my problem is: how do I compile and upload my Pico C programs to the SRV1 so that I can do this?  I'm guessing it would involve using the zAxx command to read from flash sector xx into the flash buffer, and then using the Q command to run the Pico C program in the flash buffer.  But how do I get this Pico C program into the flash buffer to begin with?  I've successfully run Pico C programs on the SRV1 interactively from my iMac using the ! command, but I don't understand how to upload an entire program at a time.
 
Of course, if there's some way to assert values on the GPIO pins using the ASCII protocol, I'll stick with that!

Thanks for the link to the Pico C forum (http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1239459317;start=all), but before posting yesterday I did actually look at that forum, and I concluded that there was something I didn't understand -- a step-by-step of how to take a Pico C program fragment, upload it to the Blackfin, and run it.  
 
So, let's say I have a socket open to the Blackfin, and I have a Pico C command like 'printf("Hello world!");' that I want to upload and run -- how (step-by-step) do I do this?