humidity1 -

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gavin beardall / Mbed 2 deprecated humidity1

main.cpp@2:5628e75c533e, 2011-10-17 (annotated)

Committer:: gbeardall
Date:: Mon Oct 17 10:41:44 2011 +0000
Revision:: 2:5628e75c533e
Parent:: 1:bdb889fd3bef

Who changed what in which revision?

User	Revision	Line number	New contents of line
gbeardall	1:bdb889fd3bef	1	/*
gbeardall	1:bdb889fd3bef	2	* humidity1
gbeardall	1:bdb889fd3bef	3	*
gbeardall	1:bdb889fd3bef	4	*/
gbeardall	1:bdb889fd3bef	5
gbeardall	2:5628e75c533e	6	/*
gbeardall	2:5628e75c533e	7	+5 --------
gbeardall	2:5628e75c533e	8	\|
gbeardall	2:5628e75c533e	9	\|
gbeardall	2:5628e75c533e	10	+-+
gbeardall	2:5628e75c533e	11	\| \| \|\
gbeardall	2:5628e75c533e	12	\| \|->----\|+\
gbeardall	2:5628e75c533e	13	\| \| \| \--+----+------
gbeardall	2:5628e75c533e	14	+-+ +- \|-/ \| \|
gbeardall	2:5628e75c533e	15	\| \| \|/ \| +-+
gbeardall	2:5628e75c533e	16	\| +--------+ \| \|
gbeardall	2:5628e75c533e	17	0v ------ +_+
gbeardall	2:5628e75c533e	18	\|--------
gbeardall	2:5628e75c533e	19	+-+
gbeardall	2:5628e75c533e	20	\| \|
gbeardall	2:5628e75c533e	21	+-+
gbeardall	2:5628e75c533e	22	\|
gbeardall	2:5628e75c533e	23
gbeardall	2:5628e75c533e	24
gbeardall	2:5628e75c533e	25
gbeardall	2:5628e75c533e	26	*/
gbeardall	2:5628e75c533e	27
gbeardall	0:dba2bcefd284	28	#include "mbed.h"
gbeardall	0:dba2bcefd284	29
gbeardall	0:dba2bcefd284	30	DigitalOut myled(LED1);
gbeardall	0:dba2bcefd284	31
gbeardall	0:dba2bcefd284	32	AnalogIn hum(p20);
gbeardall	0:dba2bcefd284	33	AnalogIn ref(p19);
gbeardall	2:5628e75c533e	34	AnalogIn tst(p18);
gbeardall	2:5628e75c533e	35
gbeardall	2:5628e75c533e	36	//Timer timer;
gbeardall	2:5628e75c533e	37
gbeardall	0:dba2bcefd284	38
gbeardall	1:bdb889fd3bef	39	int main() {
gbeardall	1:bdb889fd3bef	40	float av0 = 0.0;
gbeardall	2:5628e75c533e	41	float alpha = 0.2;
gbeardall	2:5628e75c533e	42
gbeardall	2:5628e75c533e	43	printf("\rhumidity1: %u %u\n\r", sizeof(unsigned long long), sizeof(uint64_t) );
gbeardall	2:5628e75c533e	44
gbeardall	2:5628e75c533e	45	// decimation and downsamplig to reduce noise and increment resolution
gbeardall	0:dba2bcefd284	46
gbeardall	2:5628e75c533e	47	while(1) {
gbeardall	2:5628e75c533e	48
gbeardall	2:5628e75c533e	49	// 32 - ? 8081
gbeardall	2:5628e75c533e	50	// 64 - 8 8082
gbeardall	2:5628e75c533e	51	// 128 - 6 807d
gbeardall	2:5628e75c533e	52	// 256 - 4 8071
gbeardall	2:5628e75c533e	53	// 512 - 2 805e
gbeardall	2:5628e75c533e	54	// 1024 - .3 803f
gbeardall	2:5628e75c533e	55	// 2048 - ? 8014
gbeardall	2:5628e75c533e	56	// 4096 - ? 7fe8
gbeardall	2:5628e75c533e	57	// 8192 - ? 7fca
gbeardall	2:5628e75c533e	58	// 16384 - ? 7fba
gbeardall	2:5628e75c533e	59	// 32768 - ? 7fb2
gbeardall	2:5628e75c533e	60	// 65536 - ? 7faf
gbeardall	2:5628e75c533e	61	// 131072 - ? 7fad
gbeardall	2:5628e75c533e	62
gbeardall	2:5628e75c533e	63	// Sample values and their differences
gbeardall	2:5628e75c533e	64	// 7FB7 7FC7 7FD7 7FE7 7FF7 8008 8018 8028
gbeardall	2:5628e75c533e	65	// 10 10 10 10 11 10 10
gbeardall	2:5628e75c533e	66
gbeardall	2:5628e75c533e	67	// Max conversion rate: 14KHz (~70us)
gbeardall	2:5628e75c533e	68	// ToDo
gbeardall	2:5628e75c533e	69	// many samples to create new data set
gbeardall	2:5628e75c533e	70	// different sampling frequencies, see if effect same
gbeardall	2:5628e75c533e	71	// measure raw sampling freq
gbeardall	2:5628e75c533e	72	// fourier analysis
gbeardall	2:5628e75c533e	73	// freq distribution
gbeardall	2:5628e75c533e	74	// overall and diff sized moving avg to see if effect is due to software.overflow or noise in data
gbeardall	2:5628e75c533e	75	// what does graph do at even larger sample sizes
gbeardall	2:5628e75c533e	76	// is there a temp drift?
gbeardall	2:5628e75c533e	77
gbeardall	2:5628e75c533e	78
gbeardall	2:5628e75c533e	79	//unsigned long long t = 0; // uint64_t
gbeardall	2:5628e75c533e	80	uint64_t t = 0;
gbeardall	2:5628e75c533e	81	uint64_t n = 1000; // 128/4096
gbeardall	2:5628e75c533e	82	//timer.start();
gbeardall	2:5628e75c533e	83	//float b1 = timer.read();
gbeardall	2:5628e75c533e	84	//int begin = timer.read_ms();
gbeardall	2:5628e75c533e	85	for(int i=0; i<n; ++i) {
gbeardall	2:5628e75c533e	86	//uint16_t v = tst.read_u16();
gbeardall	2:5628e75c533e	87	//uint64_t v = tst.read_u16();
gbeardall	2:5628e75c533e	88	uint64_t v = ref.read_u16();
gbeardall	2:5628e75c533e	89	//v >>= 4; // back to 12bits
gbeardall	2:5628e75c533e	90
gbeardall	2:5628e75c533e	91	t += v;
gbeardall	2:5628e75c533e	92	#if 0
gbeardall	2:5628e75c533e	93	switch((v>>4)&0x01) {
gbeardall	2:5628e75c533e	94	case 0: wait_us(7); break;
gbeardall	2:5628e75c533e	95	case 1: wait_us(17); break;
gbeardall	2:5628e75c533e	96	default: printf("?");
gbeardall	2:5628e75c533e	97	} // switch
gbeardall	2:5628e75c533e	98	#endif
gbeardall	2:5628e75c533e	99	} // for
gbeardall	2:5628e75c533e	100	//int end = timer.read_ms();
gbeardall	2:5628e75c533e	101	//float e1 = timer.read();
gbeardall	2:5628e75c533e	102	//printf("timer: %d %f %f\n\r", end-begin, e1-b1, (float)n*1000.0/(float)(end-begin) );
gbeardall	2:5628e75c533e	103
gbeardall	2:5628e75c533e	104	uint64_t x = t / n;
gbeardall	2:5628e75c533e	105	//t = t/(float)n;
gbeardall	2:5628e75c533e	106
gbeardall	2:5628e75c533e	107	printf("%llu\n\r", x);
gbeardall	2:5628e75c533e	108	//printf("%.0f\n\r", t);
gbeardall	2:5628e75c533e	109
gbeardall	2:5628e75c533e	110	//wait(4); // <<<<<<<<
gbeardall	2:5628e75c533e	111
gbeardall	2:5628e75c533e	112	//wait_us(31);
gbeardall	2:5628e75c533e	113	}
gbeardall	1:bdb889fd3bef	114
gbeardall	0:dba2bcefd284	115	while(1) {
gbeardall	0:dba2bcefd284	116
gbeardall	1:bdb889fd3bef	117	// read many times to remove noise
gbeardall	1:bdb889fd3bef	118	int n = 1000;
gbeardall	1:bdb889fd3bef	119	float h = 0.0;
gbeardall	1:bdb889fd3bef	120	float r = 0.0;
gbeardall	1:bdb889fd3bef	121	float v = 0.0;
gbeardall	1:bdb889fd3bef	122	for(int i=0; i<n; ++i) {
gbeardall	1:bdb889fd3bef	123	float h1, r1;
gbeardall	1:bdb889fd3bef	124	h1 = hum.read();
gbeardall	1:bdb889fd3bef	125	r1 = ref.read();
gbeardall	1:bdb889fd3bef	126	h += h1;
gbeardall	1:bdb889fd3bef	127	r += r1;
gbeardall	2:5628e75c533e	128	//v += 5.0*h1/r1; // convert to 5v reference
gbeardall	2:5628e75c533e	129	wait_us(100);
gbeardall	1:bdb889fd3bef	130	}
gbeardall	1:bdb889fd3bef	131	h /= n;
gbeardall	1:bdb889fd3bef	132	r /= n;
gbeardall	2:5628e75c533e	133	//v /= n;
gbeardall	0:dba2bcefd284	134
gbeardall	2:5628e75c533e	135	v = 5.0*h/r; // convert to 5v reference
gbeardall	2:5628e75c533e	136
gbeardall	2:5628e75c533e	137
gbeardall	2:5628e75c533e	138	// Exponential Moving Average
gbeardall	1:bdb889fd3bef	139	float av = av0 + alpha*(v-av0);
gbeardall	1:bdb889fd3bef	140	av0 = av;
gbeardall	0:dba2bcefd284	141
gbeardall	1:bdb889fd3bef	142	// scale to humidity%
gbeardall	1:bdb889fd3bef	143	float m = (av-0.8)/3.0*100.0;
gbeardall	0:dba2bcefd284	144
gbeardall	2:5628e75c533e	145	printf("h=%1.4f r=%1.4f %1.4fv %1.4fv %3.2f%%\n\r", h, r, v, av, m );
gbeardall	0:dba2bcefd284	146
gbeardall	0:dba2bcefd284	147	myled = 1;
gbeardall	0:dba2bcefd284	148	wait(0.2);
gbeardall	0:dba2bcefd284	149	myled = 0;
gbeardall	0:dba2bcefd284	150	wait(0.8);
gbeardall	1:bdb889fd3bef	151
gbeardall	1:bdb889fd3bef	152	} // while
gbeardall	1:bdb889fd3bef	153
gbeardall	1:bdb889fd3bef	154	} // main
gbeardall	1:bdb889fd3bef	155

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	24 Aug 2011
Imports:	5
Forks:	0
Commits:	3
Dependents:	0
Dependencies:	1
Followers:	1

main.cpp@2:5628e75c533e, 2011-10-17 (annotated)

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