USART1 et DMA cmd

tran · ‎2009-01-15

Posted on January 15, 2009 at 10:54

USART1 et DMA cmd

tran · ‎2011-05-17

Posted on May 17, 2011 at 12:59

Hello all!

My situation is :i have a buffer TxBuffer[size] that i want transfer in USART1_DR by using DMA and then transfer it into an external device.

But i can only do the transfer when i active the DMA_Cmd in the first time ( DMA and USART do it automtically). What i have to do if i want transfer one more times my buffer?

Thanks

christophe239955_st · ‎2011-05-17

Posted on May 17, 2011 at 12:59

You may use the DMA in Circular Mode. When circular mode is activated, the number of data to be transferred is automatically

reloaded with the initial value programmed during the channel configuration phase, and the DMA requests continue to be served.

This feature can be enabled using the CIRC bit in the DMA_CCRx register.

Chris

tran · ‎2011-05-17

Posted on May 17, 2011 at 12:59

ok, it worked

thanks you very much