Eric Gregori

DMA to UART serial Driver for ColdFire

Discussion created by Eric Gregori Employee on Sep 4, 2007
Latest reply on May 4, 2011 by gang chen
I wrote a DMA to UART serial driver for ColdFire.
You can get it at
This firmware is an example of how to use DMA transfers to and from the UART.
The source code is only about 200 lines, but includes 600 lines of comments. The project is for a MCF52233DEMO board, but the firmware will work on a MCF521x, MCF5223x(Ethernet), or MCF5222x(USB) MPU.


                  int main(void)
                  unsigned char Get_Byte_From_Ring() - Take one byte from RX ring buffer
                  void Use_DMA_to_Send_Message( char *null_terminated_string )
                 unsigned char Check_DMA_Message_Status()
                 DMA3_isr() - interrupt is generated only when RX buffer is full (256 bytes)
                 uart_init() - example of how to init UART from ColdFire template