ADC_spikes - Program to benchmark AnalogIn performance

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Mihail Stoyanov / Mbed 2 deprecated ADC_spikes

Program to benchmark AnalogIn performance

Dependencies: mbed

Fork of ADC_spikes by Chris Styles

main.cpp@0:62a007afbcbf, 2011-12-01 (annotated)

Committer:: chris
Date:: Thu Dec 01 16:37:07 2011 +0000
Revision:: 0:62a007afbcbf
Child:: 1:bdd134268a52

Who changed what in which revision?

User	Revision	Line number	New contents of line
chris	0:62a007afbcbf	1	#include "mbed.h"
chris	0:62a007afbcbf	2
chris	0:62a007afbcbf	3	#define NUM_SAMPLES 500000
chris	0:62a007afbcbf	4
chris	0:62a007afbcbf	5	DigitalOut myled(LED1);
chris	0:62a007afbcbf	6	Serial pc(USBTX,USBRX);
chris	0:62a007afbcbf	7
chris	0:62a007afbcbf	8	AnalogIn ain(p17);
chris	0:62a007afbcbf	9
chris	0:62a007afbcbf	10	Timer t;
chris	0:62a007afbcbf	11
chris	0:62a007afbcbf	12	int num_8;
chris	0:62a007afbcbf	13	int num_16;
chris	0:62a007afbcbf	14	int num_32;
chris	0:62a007afbcbf	15	int num_64;
chris	0:62a007afbcbf	16	int num_128;
chris	0:62a007afbcbf	17	int num_256;
chris	0:62a007afbcbf	18	int num_512;
chris	0:62a007afbcbf	19	int num_1024;
chris	0:62a007afbcbf	20	int num_2048;
chris	0:62a007afbcbf	21
chris	0:62a007afbcbf	22
chris	0:62a007afbcbf	23	int main() {
chris	0:62a007afbcbf	24
chris	0:62a007afbcbf	25	pc.baud(115200);
chris	0:62a007afbcbf	26
chris	0:62a007afbcbf	27	int num_samples = 0;
chris	0:62a007afbcbf	28
chris	0:62a007afbcbf	29	num_8 = 0;
chris	0:62a007afbcbf	30	num_16 = 0;
chris	0:62a007afbcbf	31	num_32 = 0;
chris	0:62a007afbcbf	32	num_64 = 0;
chris	0:62a007afbcbf	33	num_128 = 0;
chris	0:62a007afbcbf	34	num_256 = 0;
chris	0:62a007afbcbf	35	num_512 = 0;
chris	0:62a007afbcbf	36	num_1024 = 0;
chris	0:62a007afbcbf	37	num_2048 = 0;
chris	0:62a007afbcbf	38
chris	0:62a007afbcbf	39	/*
chris	0:62a007afbcbf	40	while (1) {
chris	0:62a007afbcbf	41	pc.printf("%f\n",ain.read());
chris	0:62a007afbcbf	42	// wait(0.1);
chris	0:62a007afbcbf	43	}
chris	0:62a007afbcbf	44	*/
chris	0:62a007afbcbf	45
chris	0:62a007afbcbf	46
chris	0:62a007afbcbf	47
chris	0:62a007afbcbf	48
chris	0:62a007afbcbf	49	// do a calibration
chris	0:62a007afbcbf	50
chris	0:62a007afbcbf	51	float AVERAGE = 0.5;
chris	0:62a007afbcbf	52
chris	0:62a007afbcbf	53	// taking an average
chris	0:62a007afbcbf	54	pc.printf("Taking an average over %d samples\n",NUM_SAMPLES);
chris	0:62a007afbcbf	55	while (num_samples < NUM_SAMPLES) {
chris	0:62a007afbcbf	56	float r = ain.read();
chris	0:62a007afbcbf	57
chris	0:62a007afbcbf	58	if ((r > 0.49) && (r < 0.51)) {
chris	0:62a007afbcbf	59	AVERAGE = (AVERAGE + r) /2.0;
chris	0:62a007afbcbf	60	num_samples++;
chris	0:62a007afbcbf	61	}
chris	0:62a007afbcbf	62
chris	0:62a007afbcbf	63	}
chris	0:62a007afbcbf	64	pc.printf("Average = %f\n",AVERAGE);
chris	0:62a007afbcbf	65
chris	0:62a007afbcbf	66
chris	0:62a007afbcbf	67
chris	0:62a007afbcbf	68	pc.printf("Reading floats\n");
chris	0:62a007afbcbf	69	num_samples = 0;
chris	0:62a007afbcbf	70	t.reset();
chris	0:62a007afbcbf	71	t.start();
chris	0:62a007afbcbf	72
chris	0:62a007afbcbf	73	while (num_samples < NUM_SAMPLES) {
chris	0:62a007afbcbf	74	float a = ain.read();
chris	0:62a007afbcbf	75
chris	0:62a007afbcbf	76
chris	0:62a007afbcbf	77	if (a > (AVERAGE + 0.5000))
chris	0:62a007afbcbf	78	{num_2048++;} // > 2048 lsb
chris	0:62a007afbcbf	79	else if (a > (AVERAGE + 0.2500))
chris	0:62a007afbcbf	80	{num_1024++;} // > 1024 lsb
chris	0:62a007afbcbf	81	else if (a > (AVERAGE + 0.0625))
chris	0:62a007afbcbf	82	{num_512++;} // > 512 lsb
chris	0:62a007afbcbf	83	else if (a > (AVERAGE + 0.0312))
chris	0:62a007afbcbf	84	{num_256++;} // > 256 lsb
chris	0:62a007afbcbf	85	else if (a > (AVERAGE + 0.0312))
chris	0:62a007afbcbf	86	{num_128++;} // > 128 lsb
chris	0:62a007afbcbf	87	else if (a > (AVERAGE + 0.0156))
chris	0:62a007afbcbf	88	{num_64++;} // > 64 lsb
chris	0:62a007afbcbf	89	else if (a > (AVERAGE + 0.0078))
chris	0:62a007afbcbf	90	{num_32++;} // > 32 lsb
chris	0:62a007afbcbf	91	else if (a > (AVERAGE + 0.0039))
chris	0:62a007afbcbf	92	{num_16++;} // > 16 lsb
chris	0:62a007afbcbf	93	else if (a > (AVERAGE + 0.0019))
chris	0:62a007afbcbf	94	{num_8++;} // > 8 lsb
chris	0:62a007afbcbf	95
chris	0:62a007afbcbf	96	num_samples++;
chris	0:62a007afbcbf	97	}
chris	0:62a007afbcbf	98
chris	0:62a007afbcbf	99	t.stop();
chris	0:62a007afbcbf	100	pc.printf("Time taken for %d samples was %fs\n",NUM_SAMPLES,t.read());
chris	0:62a007afbcbf	101	pc.printf("over 8 lsb = %d\n",num_8);
chris	0:62a007afbcbf	102	pc.printf("over 16 lsb = %d\n",num_16);
chris	0:62a007afbcbf	103	pc.printf("over 32 lsb = %d\n",num_32);
chris	0:62a007afbcbf	104	pc.printf("over 64 lsb = %d\n",num_64);
chris	0:62a007afbcbf	105	pc.printf("over 128 lsb = %d\n",num_128);
chris	0:62a007afbcbf	106	pc.printf("over 256 lsb = %d\n",num_256);
chris	0:62a007afbcbf	107	pc.printf("over 512 lsb = %d\n",num_512);
chris	0:62a007afbcbf	108	pc.printf("over 1024 lsb = %d\n",num_1024);
chris	0:62a007afbcbf	109	pc.printf("over 2048 lsb = %d\n",num_2048);
chris	0:62a007afbcbf	110
chris	0:62a007afbcbf	111
chris	0:62a007afbcbf	112
chris	0:62a007afbcbf	113
chris	0:62a007afbcbf	114
chris	0:62a007afbcbf	115	/*
chris	0:62a007afbcbf	116	pc.printf("Reading _u16\n");
chris	0:62a007afbcbf	117	num_samples = 0;
chris	0:62a007afbcbf	118	t.reset();
chris	0:62a007afbcbf	119	t.start();
chris	0:62a007afbcbf	120	while (num_samples < NUM_SAMPLES) {
chris	0:62a007afbcbf	121	int a = ain.read_u16();
chris	0:62a007afbcbf	122	num_samples++;
chris	0:62a007afbcbf	123	}
chris	0:62a007afbcbf	124	t.stop();
chris	0:62a007afbcbf	125	pc.printf("Time taken for %d samples was %fs\n",NUM_SAMPLES,t.read());
chris	0:62a007afbcbf	126
chris	0:62a007afbcbf	127	*/
chris	0:62a007afbcbf	128
chris	0:62a007afbcbf	129
chris	0:62a007afbcbf	130	}

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	29 May 2012
Imports:	7
Forks:	0
Commits:	4
Dependents:	0
Dependencies:	1
Followers:	37

main.cpp@0:62a007afbcbf, 2011-12-01 (annotated)

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