ADC: RingBufferDMA.h Source File

ADC 8.0 Analog to Digital Conversor library for the Teensy 4 microprocessor

RingBufferDMA.h
1 /* Teensy 4, 3.x, LC ADC library
2 * https://github.com/pedvide/ADC
3 * Copyright (c) 2019 Pedro Villanueva
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be
14 * included in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
20 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
21 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE.
24 */
25
26 #ifndef RINGBUFFERDMA_H
27 #define RINGBUFFERDMA_H
28
29 #include <Arduino.h> // for digitalWrite
30 #include "DMAChannel.h"
31
32
35 class RingBufferDMA
36 {
37 public:
39 RingBufferDMA(volatile int16_t* elems, uint32_t len, uint8_t ADC_num = 0);
40
42 ~RingBufferDMA();
43
45 bool isFull();
46
48 bool isEmpty();
49
51 int16_t read();
52
54 void start(void (*call_dma_isr)(void));
55
57
59 void write();
60
62 uint16_t size() {return b_size; }
63
65 volatile int16_t* const buffer() {return p_elems;}
66
68 DMAChannel* dmaChannel;
69
70
71 // the buffer needs to be aligned, so use malloc instead of new
72 // see http://stackoverflow.com/questions/227897/solve-the-memory-alignment-in-c-interview-question-that-stumped-me/
73 //uint8_t alignment;
74 //void *p_mem;
75
77 uint16_t b_start;
79 uint16_t b_end;
80
82 volatile int16_t* const p_elems;
83
84 protected:
85 private:
86
87
88
90 uint16_t b_size;
91
93 uint8_t ADC_number;
94
96 uint16_t increase(uint16_t p);
97
98 volatile uint32_t* const ADC_RA;
99
100
101
102
103 };
104
105
106 #endif // RINGBUFFERDMA_H
RingBufferDMA::b_end
uint16_t b_end
End pointer: Write here.
Definition: RingBufferDMA.h:79
RingBufferDMA::write
void write()
Write a value into the buffer.
RingBufferDMA::isFull
bool isFull()
Returns true if the buffer is full.
RingBufferDMA::b_start
uint16_t b_start
Start pointer: Read here.
Definition: RingBufferDMA.h:77
RingBufferDMA::size
uint16_t size()
Length of the buffer.
Definition: RingBufferDMA.h:62
RingBufferDMA::RingBufferDMA
RingBufferDMA(volatile int16_t *elems, uint32_t len, uint8_t ADC_num=0)
Constructor, buffer has a size len and stores the conversions of ADC number ADC_num.
RingBufferDMA::start
void start(void(*call_dma_isr)(void))
Start DMA operation.
RingBufferDMA::~RingBufferDMA
~RingBufferDMA()
Destructor.
RingBufferDMA::p_elems
volatile int16_t *const p_elems
Pointer to the elements of the buffer.
Definition: RingBufferDMA.h:82
RingBufferDMA::dmaChannel
DMAChannel * dmaChannel
DMAChannel to handle all low level DMA code.
Definition: RingBufferDMA.h:68
RingBufferDMA::buffer
volatile int16_t *const buffer()
Pointer to the data.
Definition: RingBufferDMA.h:65
RingBufferDMA
Definition: RingBufferDMA.h:35
RingBufferDMA::isEmpty
bool isEmpty()
Returns true if the buffer is empty.
RingBufferDMA::read
int16_t read()
Read a value from the buffer, make sure it's not emtpy by calling isEmpty() first.