LPCXpresso54618

This example shows how to use the DMA driver to implement a double buffer receive scheme from the USARTThe example shows the double buffer constructed using two descriptors (g_pingpong_desc). These descriptors are cycled from one to the other.Things to note- The descriptors of the ping pong transfer need to be aligned to size 16- The inital transfer will perform the same job as first descriptor of ping pong, so the first linkeage is to go to g_pingpong_desc[1]- g_pingpong_desc[1] then chains the g_pingpong_desc[0] as the next descriptor- The properties are set up such that g_pingpong_desc[0] (and the initial configuration uses INTA to signal back to the callback)- g_pingpong_desc[1] uses INTB to signal to the callback- The scheduled callback uses this information to know which data was last writtenA note on PerformanceThe intent of this example is to illustrate how a double-buffer scheme can be implemented using the dma. The performance of this example will be limited to how quickly the echo printer can read-out the data from the ping pong buffer and display it. This means that the example will work well if characters are entered at a rate where the DMA callback to echo the string can keep up with the input stream. Connecting the USARTRX to a continuous fast speed will cause the DMA to fall behind.

The usart_dma ring buffer example shows how to use usart driver with DMA:In this example, one usart instance connect to PC through usart, the board will send back all characters that PC send to the board.

The usart_dma example shows how to use usart driver with DMA:In this example, one usart instance connect to PC through usart, the board willsend back all characters that PC send to the board.Note: The example echo every 8 characters, so input 8 characters every time.

The uart_functioncal_interrupt example shows how to use uart driver functionalAPI to receive data with interrupt method:In this example, one uart instance connect to PC through uart, the board willsend back all characters that PC send to the board.

The uart_interrupt_ring_buffer example shows how to use uart driver in interrupt way withRX ring buffer enabled:In this example, one uart instance connect to PC through uart, the board willsend back all characters that PC send to the board.Note: The example echo every 8 characters, so input 8 characters every time.

The uart_interrupt example shows how to use uart driver in interrupt way:In this example, one uart instance connect to PC through uart, the board willsend back all characters that PC send to the board.Note: The example echo every 8 characters, so input 8 characters every time.

The uart_polling example shows how to use uart driver in polling way:In this example, one uart instance connect to PC through uart, the board will send back all characters that PCsend to the board.

The usart synchronous transfer example shows how to use usart driver in synchronous way.

The usart synchronous transfer example shows how to use usart driver in synchronous way.

The purpose of this demo is to show wakeup from deep sleep mode using MicroTick timer.The demo sets the MicroTick Timer as a wake up source and puts the device in deep-sleep mode. The MicroTick timer wakes up the device.