printf() inside interrupt routine?

[Kevin Watson]

Originally Posted by Nathan

...I was debugging my driver and wanted to be able to see every byte printed out in the order it arrived.

Why not send the data right back out the other serial port?

-Kevin

[Nathan]

Originally Posted by Kevin Watson

Why not send the data right back out the other serial port?

-Kevin

I thought that's what printf did?

[Adam Shapiro]

Originally Posted by Nathan

I thought that's what printf did?

Printf converts the data you pass to it into a human-readable string format. For instance, the value 100 would be converted into the following three characters: '1' '0' '0'. What Kevin is suggesting is for you to simply send the byte values themselves out of the serial port. This can be done very quickly and won't impact the ISR very much. You can then read those values into the computer and view them at your leisure, or record them and process them with an additional application (which may be quite useful for what it seems you're trying to do).

[Kevin Watson]

Originally Posted by Nathan

I thought that's what printf did?

As Adam pointed out, and assuming you're using my serial port driver, it's as simple as this:

 // first, find out how much data, if any, is present in 
 // serial port 1's received data queue?
 byte_count = Serial_Port_One_Byte_Count();
 
 // have we received any data?
 if(byte_count > 0)
 {
  // we have fresh data, so read each received byte one at a time
  for(j = 0; j < byte_count; j++)
  {
   // get the next data byte
   data = Read_Serial_Port_One();
 
   // send it out the other serial port
   Write_Serial_Port_Two(data);
 
  // work with camera data here
  }
}

-Kevin