From SPI to RS232

[mrad13]

hi friends
I receive data on SPI interface ( 27 bytes to be exact ) and i want to transmit them on the RS232 to PC. How i can do this? It's possible to give me an example ? I'm newbie :D

Thanks a lot

[Mike Walne]

CCS provides examples of both SPI and RS232.
Plus there is loads of relevant code on this forum.

Mike

[ckielstra]

You didn't give all details, but it is very likely you'll have to add some kind of buffering. On SPI it is very common to have bit rates in the order of Mbits per second where RS232 often stops at 115kbaud.

Search the internet for the concept of a 'ring buffer', it is one powerful method for buffering data. An implementation of the ring buffer in RS232 transmission can be found in the CCS example directory on your computer and is named ex_stisr.c

I assume your PIC is the master on the SPI bus? Then reading the SPI data is easy and can be implemented without interrupts. Again, examples can be found in the CCS example directory and on this forum.

[PCM programmer]

This thread has a sample program which puts incoming SPI data in a
ring buffer:
http://www.ccsinfo.com/forum/viewtopic.php?t=26888
spi_kbhit - Tells if data is available in the ring buffer.
spi_bgetc - Is used to get a byte of data from the ring buffer.