Steins7
fd33003e26
DMA buffers now work reliably with USART. The DMA api has changed to make it more efficient code-size-wise. This may, however, complicate things when implementating powersaving features
57 lines
1.7 KiB
C
57 lines
1.7 KiB
C
/** @file dma_cbuf.h
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* Module handling Direct Memory Access controller's circular system
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*
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* The module provides a convenient tool to receive data from a peripheral in a
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* buffered, low-latency, low-cpu usage, non-blocking way
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*/
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#ifndef _DMA_CBUF_H_
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#define _DMA_CBUF_H_
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//--includes--------------------------------------------------------------------
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#include "../drv/dma.h"
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//--type definitions------------------------------------------------------------
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/**
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* Struct used by the circular buffer system. This system allows bufferized
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* reads to a peripheral with no latency, minimal cpu usage and customisable
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* buffer sizes
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*/
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struct DmaCircBuffer {
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volatile void* buffer; //the buffer to use as a circular buffer
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uint16_t size; //the size of the buffer
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uint16_t begin; //pointer to the current begin of the buffer
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enum DmaPeriph dma;
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enum DmaChannel channel;
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bool dma_looped; //whether the DMA looped or not (buffer overflow)
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};
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//--functions-------------------------------------------------------------------
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/**
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* Configure a DMA circular buffer for a single DMA channel. A standard buffer
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* is used a base to construct a circular buffer, supplied in data by DMA
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* tranfers from a peripheral. The DMA's priority is given as parameters.
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* The peripheral's specific configuration must be handled separately.
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*
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* Once this function is called, the system will start running right away and
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* will stay running until manually stopped
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*/
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void dma_cbuf_configure(volatile struct DmaCircBuffer* buffer,
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const struct DmaParam* param, enum DmaConfig priority,
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volatile void* raw_buffer, uint16_t buffer_size);
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uint32_t dma_cbuf_read_byte(volatile struct DmaCircBuffer* buffer,
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uint8_t* byte);
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#endif //_DMA_CBUF_H_
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