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David Buck / Mbed 2 deprecated voltmeter

main.cpp@0:d322a5241da8, 2009-12-16 (annotated)

Committer:: Kaikestu
Date:: Wed Dec 16 12:04:23 2009 +0000
Revision:: 0:d322a5241da8

Who changed what in which revision?

User	Revision	Line number	New contents of line
Kaikestu	0:d322a5241da8	1	//main.cpp
Kaikestu	0:d322a5241da8	2	/****************************************************************
Kaikestu	0:d322a5241da8	3	* Include files
Kaikestu	0:d322a5241da8	4	****************************************************************/
Kaikestu	0:d322a5241da8	5	#include "header.h"
Kaikestu	0:d322a5241da8	6
Kaikestu	0:d322a5241da8	7	/****************************************************************
Kaikestu	0:d322a5241da8	8	* data values
Kaikestu	0:d322a5241da8	9	****************************************************************/
Kaikestu	0:d322a5241da8	10	#define cal -200 // calibration value
Kaikestu	0:d322a5241da8	11
Kaikestu	0:d322a5241da8	12	int A2D_in; /* input variable */
Kaikestu	0:d322a5241da8	13	int V_in; /* input voltage */
Kaikestu	0:d322a5241da8	14	int V_unit; /* voltage units value */
Kaikestu	0:d322a5241da8	15	int V_unit_old; // previous unit value
Kaikestu	0:d322a5241da8	16	int V_in_dec; /* input voltage decimal value */
Kaikestu	0:d322a5241da8	17	int V_dec; /* voltage decimal value */
Kaikestu	0:d322a5241da8	18	int V_dec_old; // previous decimal value
Kaikestu	0:d322a5241da8	19	float x;
Kaikestu	0:d322a5241da8	20
Kaikestu	0:d322a5241da8	21	/****************************************************************
Kaikestu	0:d322a5241da8	22	* Main part of the program
Kaikestu	0:d322a5241da8	23	****************************************************************/
Kaikestu	0:d322a5241da8	24	int main()
Kaikestu	0:d322a5241da8	25	{
Kaikestu	0:d322a5241da8	26
Kaikestu	0:d322a5241da8	27	ADC_init();
Kaikestu	0:d322a5241da8	28	LCD_init();
Kaikestu	0:d322a5241da8	29	LCD_displayV();
Kaikestu	0:d322a5241da8	30
Kaikestu	0:d322a5241da8	31	while(1){ /* infinite loop */
Kaikestu	0:d322a5241da8	32
Kaikestu	0:d322a5241da8	33	A2D_in=ADC_read();
Kaikestu	0:d322a5241da8	34	V_in=A2D_in33; / calculate voltage from 8-bit ADC input 0xFF = 3.3V */
Kaikestu	0:d322a5241da8	35	// all voltage values multiplied by 10 to allow integer manipulation
Kaikestu	0:d322a5241da8	36
Kaikestu	0:d322a5241da8	37
Kaikestu	0:d322a5241da8	38	//**************** calculate voltage unit = 0-5V ****************************
Kaikestu	0:d322a5241da8	39	if(V_in >= 50*255) // if greater than 5V then unit to display = 5
Kaikestu	0:d322a5241da8	40	{
Kaikestu	0:d322a5241da8	41	V_unit = 0x05;
Kaikestu	0:d322a5241da8	42	V_in_dec = 0; // if unit = 5 then decimal must be 0 (5.0V=max)
Kaikestu	0:d322a5241da8	43	}
Kaikestu	0:d322a5241da8	44	else if(V_in > 40*255) // else if greater than 4V then unit to display = 4
Kaikestu	0:d322a5241da8	45	{
Kaikestu	0:d322a5241da8	46	V_unit = 0x04;
Kaikestu	0:d322a5241da8	47	V_in_dec = V_in-40*256; // calculate remainder for decimal processing
Kaikestu	0:d322a5241da8	48	}
Kaikestu	0:d322a5241da8	49	else if(V_in > 30*255) // else if greater than 3V then unit to display = 3
Kaikestu	0:d322a5241da8	50	{
Kaikestu	0:d322a5241da8	51	V_unit = 0x03;
Kaikestu	0:d322a5241da8	52	V_in_dec = V_in-30*256;
Kaikestu	0:d322a5241da8	53	}
Kaikestu	0:d322a5241da8	54	else if(V_in > 20*255) // else if greater than 2V then unit to display = 2
Kaikestu	0:d322a5241da8	55	{
Kaikestu	0:d322a5241da8	56	V_unit = 0x02;
Kaikestu	0:d322a5241da8	57	V_in_dec = V_in-20*256;
Kaikestu	0:d322a5241da8	58	}
Kaikestu	0:d322a5241da8	59	else if(V_in > 10*255) // else if greater than 1V then unit to display = 1
Kaikestu	0:d322a5241da8	60	{
Kaikestu	0:d322a5241da8	61	V_unit = 0x01;
Kaikestu	0:d322a5241da8	62	V_in_dec = V_in-10*256;
Kaikestu	0:d322a5241da8	63	}
Kaikestu	0:d322a5241da8	64	else // else unit to display = 0
Kaikestu	0:d322a5241da8	65	{
Kaikestu	0:d322a5241da8	66	V_unit = 0x00;
Kaikestu	0:d322a5241da8	67	V_in_dec = V_in;
Kaikestu	0:d322a5241da8	68	}
Kaikestu	0:d322a5241da8	69
Kaikestu	0:d322a5241da8	70	// if unit has changed, then display the new unit on the screen
Kaikestu	0:d322a5241da8	71	if (V_unit!= V_unit_old){
Kaikestu	0:d322a5241da8	72
Kaikestu	0:d322a5241da8	73	// start of line 2
Kaikestu	0:d322a5241da8	74	FIO2CLR0=0x02; /* set RS to 'instruction' */
Kaikestu	0:d322a5241da8	75	FIO0PIN2=0xC6; /* set address to line 2 units position*/
Kaikestu	0:d322a5241da8	76	toggle_enable();
Kaikestu	0:d322a5241da8	77	FIO2SET0=0x02; /* set RS to 'data' */
Kaikestu	0:d322a5241da8	78
Kaikestu	0:d322a5241da8	79	FIO0PIN2=(0x30+V_unit); // display unit value on screen
Kaikestu	0:d322a5241da8	80	toggle_enable();
Kaikestu	0:d322a5241da8	81	V_unit_old=V_unit;
Kaikestu	0:d322a5241da8	82	}
Kaikestu	0:d322a5241da8	83
Kaikestu	0:d322a5241da8	84
Kaikestu	0:d322a5241da8	85	//**************** calculate decimal value = .0 - .9 ****************************
Kaikestu	0:d322a5241da8	86	if(V_in_dec <=260+cal)
Kaikestu	0:d322a5241da8	87	V_dec = 0x00;
Kaikestu	0:d322a5241da8	88	if(V_in_dec > 260+cal) // decimal value must be between 0 and 2550 (ie 255*10)
Kaikestu	0:d322a5241da8	89	V_dec = 0x01;
Kaikestu	0:d322a5241da8	90	if(V_in_dec > 510+cal) // calibration value allows an amount of simple tuning
Kaikestu	0:d322a5241da8	91	V_dec = 0x02; // any error should be linear, but maybe with an offset
Kaikestu	0:d322a5241da8	92	if(V_in_dec > 770+cal) // a complete look-up table would be better though!
Kaikestu	0:d322a5241da8	93	V_dec = 0x03;
Kaikestu	0:d322a5241da8	94	if(V_in_dec > 1120+cal)
Kaikestu	0:d322a5241da8	95	V_dec = 0x04;
Kaikestu	0:d322a5241da8	96	if(V_in_dec > 1280+cal)
Kaikestu	0:d322a5241da8	97	V_dec = 0x05;
Kaikestu	0:d322a5241da8	98	if(V_in_dec > 1530+cal)
Kaikestu	0:d322a5241da8	99	V_dec = 0x06;
Kaikestu	0:d322a5241da8	100	if(V_in_dec > 1780+cal)
Kaikestu	0:d322a5241da8	101	V_dec = 0x07;
Kaikestu	0:d322a5241da8	102	if(V_in_dec > 2040+cal)
Kaikestu	0:d322a5241da8	103	V_dec = 0x08;
Kaikestu	0:d322a5241da8	104	if(V_in_dec > 2300+cal)
Kaikestu	0:d322a5241da8	105	V_dec = 0x09;
Kaikestu	0:d322a5241da8	106
Kaikestu	0:d322a5241da8	107	// if decimal value has changed then update display
Kaikestu	0:d322a5241da8	108	if (V_dec!= V_dec_old){
Kaikestu	0:d322a5241da8	109
Kaikestu	0:d322a5241da8	110	// start of line 2 */
Kaikestu	0:d322a5241da8	111	FIO2CLR0=0x02; /* set RS to 'instruction' */
Kaikestu	0:d322a5241da8	112	FIO0PIN2=0xC8; /* set address to line 2 */
Kaikestu	0:d322a5241da8	113	toggle_enable();
Kaikestu	0:d322a5241da8	114	FIO2SET0=0x02; /* set RS to 'data' */
Kaikestu	0:d322a5241da8	115
Kaikestu	0:d322a5241da8	116	FIO0PIN2=(0x30+V_dec);
Kaikestu	0:d322a5241da8	117	toggle_enable();
Kaikestu	0:d322a5241da8	118	V_dec_old=V_dec;
Kaikestu	0:d322a5241da8	119	}
Kaikestu	0:d322a5241da8	120	}
Kaikestu	0:d322a5241da8	121
Kaikestu	0:d322a5241da8	122	} /* end main() */

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	16 Dec 2009
Imports:	72
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	2

main.cpp@0:d322a5241da8, 2009-12-16 (annotated)

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