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Can anyone please supply me a sample flowchart for a standard set up menu controlled by 3-4 buttons (Menu, Up, Down and possibly Enter) as follows.

This involves pressing the Menu button, displaying menu text on a 16x2 LCD, scrolling menu with Up and Down, select an on screen value with Enter or Menu, moving to next menu item. This calibrates my temperature sensors. Jump to different bits of code depending on which menu item is selected, as it also determines the mode of operation of my temperature controller. I need to decide how to read a switch, when to pause before the next press, how to debounce, how to scroll the menu, etc.

It’s for a 16F876A PIC but just about any PIC or even non PIC should be able to use the same flowchart. It’s a bit like the setup menu you get on a modern PC LCD monitor.

Many projects will have a setup menu something like this but I can’t find a sample flowchart for one. I am completly new to Flowcode so I am sure it's easy, but not for me!

Hello

Sorry I cant really help with this project. You should be able to learn how to do all of the functions from pulling bits of sample code of the internet.

Remember Google is a programmers best resource.

Google turned up http://www.microchipc.com/sourcecode/#ds1821 which seems to have roughly what I want but it's in C language and I ideally wanted it in flowcharts.

If you post the C code then it should be fairly easy to convert it into a flowchart.

This I think is the C for the menu. I need something similar for my project which also has a keypad and LCD (2 x 16 ), but only have 4 buttons to read (Menu, Up, Down and Enter)> So if this code was converted to a flowchart I can enter it into my programme and edit it to suit.

http://www.microchipc.com/sourcecode/#LCDkeypad LCD and Keypad project lists other related files if you need them.

Regards

//******************************************************************
// lcdkey2.C
//
// Firmware Version 2.01 For the LCD & KEYPAD Controler
//
// Driver software for the LCD and Keypad Interface for
// the High Speed Pulse Generator.
// I/O is using Parallel Slave Port interface.
// Data written to port from outside is displayed on LCD
// Data read from the port is the last key pressed.
//
// If all 4 Menu buttons pressed - a game (or something may appear)
//
// Author: Michael Pearce
// Electronics Workshop, Chemistry Department
// University of Canterbury
//
// Started: 5 November 1998
//
//******************** UPDATE INFORMATION **************************
// Version 2.01 12 November 1998
// Made LCD_L0 and LCD_L1 Clear the line first.
//
//******************************************************************

#include <pic.h>

#include <string.h>

#define XTAL_FREQ 8MHZ
#include "delay.h"
#include "delay.c"
#include "lcd.h"
#include "lcd.c"
#include "stdio.h"

#define KeyAddr PORTC
#define KeyInPort PORTB

#define SCROLLDELAY 100 //-- ms Delay
#define KEYDELAY 100 //-- us Delay between addressing and reading

//********* LCD CONTROL COMMANDS *********
#define LCD_CLS 0x10 //-- Clear Screen
#define LCD_CR 0x11 //-- Carrage Return
#define LCD_LF 0x12 //-- New Line
#define LCD_CRLF 0x13 //-- CR and NL
#define LCD_BEEP 0x14 //-- Makes a beep!!
#define LCD_L0 0x15 //-- Goes to start of Line 0
#define LCD_L1 0x16 //-- Goes to start of Line 1
#define LCD_PUTCH 0x1D //-- Puts next char direct to LCD bypass Buff
#define LCD_GOTO 0x1E //-- Moves Cursor to next byte location
#define LCD_SHOW 0x1F //-- Update the display
//****************************************


#define BITNUM(adr, bit) ((unsigned)(&adr)*8+(bit))
static bit Beeper @ BITNUM(PORTC, 3); //- Beeper Output pin
static bit ChipSel @ BITNUM(PORTE, 2); //- Port Select Pin
static bit TChipSel @ BITNUM(TRISE, 2);

//------- FLAGS ----------
bit NewData;
bit BeepNow;
bit GotoCommand;
bit GotoNew;
bit PutchCommand;
bit PutchNew;

//------- Global Variables, Buffers etc ----------
unsigned char Buffer[41]="Waiting for data.\0 \0";
unsigned char Head,count,GotoData,PutchData;
unsigned char KeyPressed,LastKeyPressed;

//------- Functions Used in Program --------
void interrupt GlobalInterrupt(void);
unsigned char KeyRead(void);
char DecodeKey(char keycode);
void DisplayData(void);
void Beep(char time);
//void Beep(void);
//void RunGame(void);
void ScrollMessage(unsigned char row,const char Message[]);


//**********************************************************************
//Main
//**********************************************************************
void main(void)
{
//-- Setup Variables --
Beeper=0;
NewData=0;
Head=0;
BeepNow=0;
GotoCommand=0;
GotoNew=0;
GotoData=21;

//-- Set up Ports --
TRISA=0xCF; //-- Control Pins PA4,PA5 as output
TRISB=0xF0; //-- Port B bit 0 to 3 as output
TRISC=0xF0; //-- bits 0 - 2 used for keyboard array bit 3 for Beep
TRISD=0xFF; //-- PSP configured as input
TRISE=0x07; //-- PSP Controls as input
PORTD=0x00; //-- NULL Output to start with

//-- Set Chip Sel Pin High to indicate Busy to the master
ChipSel=1;
TChipSel=0;


//-- Set Up Interrupts --
PSPMODE=0; //-- Disable the PSP Mode
PSPIE=0; //-- Disable PSP Interrupt
PSPIF=0; //-- Clear Interrupt Flag
PEIE=1; //-- Enable Peripheral Interrupts
GIE=1; //-- Enable Global Interrupts

//-- Initialise the LCD --
lcd_init();
lcd_clear();
// ScrollMessage(0," LCD & Keypad Driver");
// ScrollMessage(1," Firmware Version 2.01 ");
lcd_puts("LCD & Keypad Driver");
lcd_goto(40);
lcd_puts("Version 2.01.1");
DelayMs(200);
Beep(100);
Beep(100);
Beep(60);
Beep(60);
Beep(60);
Beep(200);
DisplayData();

//-- Signal to the Master controller to tell it that ready to recieve!!
ChipSel=0; //- Take Pin Low For 10ms
DelayMs(20);
PSPIE=1; //-- Enable PSP Interrupts
TChipSel=1; //- Back into High Impedance State
PSPMODE=1; //-- Enable PSP Mode

//-- Main Program Loop --
while(1)
{
if(NewData==1)
{
NewData=0;
DisplayData();
}
if(GotoNew==1) //-- Move Cursor to selected Position
{
GotoNew=0;
lcd_goto(GotoData);
}
if(PutchNew==1) //-- Put Character Directly to LCD Bypassing Buffer
{
PutchNew=0;
putch(PutchData);
}
if(BeepNow==1)
{
Beep(80);
// Beep();
BeepNow=0;
}
KeyPressed=KeyRead();
if(KeyPressed != 0)
{
KeyPressed=DecodeKey(KeyPressed);
if(KeyPressed != LastKeyPressed)
{
Beep(50);
LastKeyPressed=KeyPressed;
PORTD=KeyPressed;
}
if(KeyPressed==0xFF)
{
Beep(100);
Beep(50);
Beep(200);
// RunGame(); //-- All 4 menu keys were depressed
}
}
else
{
LastKeyPressed=0; //-- Key has been released so allow re pressing
}
}
}
//******************* END OF Main

//**********************************************************************
//GlobalInterrupt - exactly what it says!!
//**********************************************************************
void interrupt GlobalInterrupt(void)
{
char Icount,TempD;
if(PSPIF)
{
if(IBF) // Input Buffer Full
{
TempD=PORTD;
switch(TempD)
{
default:
if(GotoCommand==1)
{
GotoData=TempD;
GotoCommand=0;
GotoNew=1;
break;
}
if(PutchCommand==1)
{
PutchData=TempD;
PutchNew=1;
PutchCommand=0;
break;
}
Buffer[Head++]=TempD; //-- Add Data to the Buffer and point to next
if(Head < 40) break; //-- If not off the end then exit ...
Head=20; //-- ... else CR!
break;

//**************************************
case LCD_CRLF: //-- Combination of CR and LF
if(Head < 20)
{
Head=0;
}
else
{
Head=20;
}

//**************************************
case LCD_LF: //-- Line Feed
if(Head >=20)
{
for(Icount=0;Icount<20;Icount++)
{
Buffer[Icount]=Buffer[Icount+20];
Buffer[Icount+20]=0; //-- Clear the data out
}
}
else
{
Head+=20;
}
break;

//**************************************
case LCD_CR: //-- Carrage Return
if(Head < 20)
{
Head=0;
}
else
{
Head=20;
}
break;

//**************************************
case LCD_BEEP: //-- Force A Beep
BeepNow=1;
break;

//**************************************
case LCD_CLS: //-- Clear the buffer
for(Icount=0;Icount<40;Icount++)
{
Buffer[Icount]=0;
}

//**************************************
case LCD_L0: //-- Go to Start of 1st Line
Head=0; //-- Also Clear the Line
for(Icount=0;Icount<20;Icount++) Buffer[Icount]=0;
break;

//**************************************
case LCD_L1: //-- Go to Start of 2nd Line
Head=20; //-- Also Clear the Line
for(Icount=20;Icount<40;Icount++) Buffer[Icount]=0;
break;

//**************************************
case LCD_SHOW: //-- Update the Display
NewData=1;
break;

//**************************************
case LCD_GOTO: //-- Put Cursor to location
GotoCommand=1; //-- Indicated by next byte
break;

//**************************************
case LCD_PUTCH: //-- Put next character directly to LCD
PutchCommand=1; //-- By Passing the Buffer
break;
}
}

if(!OBF) // Output Buffer has been read
{
PORTD=0x00; // Put Null into buffer to indicate no key pressed
// LastKeyPressed=0; // Allow Beep again on same key
}
PSPIF=0;
}
}
//******************* END OF GlobalInterrupt

//**********************************************************************
//KeyRead
//**********************************************************************
unsigned char KeyRead(void)
{
unsigned char line,data,result=0;
for(line=0;line <8;line++)
{
KeyAddr=line; //-- Set Row To Read
DelayUs(KEYDELAY);
data = KeyInPort; //-- Read in the data
data = data >> 4; //-- shift to lower nibble
data |= 0xF0; //-- set upper nibble to 1s
data ^= 0xFF; //-- invert everything (XOR)
if(data !=0)
{
result=line<<4; //-- Put line number in upper nibble
result+=data; //-- Put Row Bit pattern in lower nibble
line=10; //-- Terminate the loop
}
}
DelayUs(KEYDELAY); //-- We Bit More Delay
return(result); //-- Return the result
}
//******************* END OF KeyRead

//**********************************************************************
//DecodeKey
//**********************************************************************
char DecodeKey(char keycode)
{
switch(keycode)
{
case 1:
return('D');
case 2:
return('E');
case 4:
return('0');
case 8:
return('C');

case 17:
return('R');
case 18:
return('3');
case 20:
return('2');
case 24:
return('1');

case 33:
return('L');
case 34:
return('6');
case 36:
return('5');
case 40:
return('4');

case 49:
return('U');
case 50:
return('9');
case 52:
return('8');
case 56:
return('7');

case 81:
return('M');
case 82:
return('a');
case 84:
return('b');
case 88:
return('c');

case 95: //-- all function keys hit.
return(0xFF);

default:
break;
}
return(0);
}
//******************* END OF DecodeKey

//**********************************************************************
//DisplayData - Displays the Buffer on the LCD Display
//**********************************************************************
void DisplayData(void)
{
// unsigned char count;
lcd_clear(); //-- Clear the LCD
lcd_goto(0);
for(count=0;count<20;count++) //-- Display the first line
{
if(Buffer[count]==0)
{
count=19; //-- Check for end of string character
}
else
{
putch(Buffer[count]); //-- Display Character on screen
}
}
lcd_goto(40); //-- Move Cursor to second Line
for(;count<40;count++) //-- Display the second line
{
if(Buffer[count]==0)
{
count=40; //-- Check for end of string character
}
else
{
putch(Buffer[count]); //-- Display Character on screen
}
}
// lcd_goto(21); //-- Put cursor off the screen
}
//******************* END OF DisplayData

//**********************************************************************
//Beep - Does a small Beep using the SCL Pin
//**********************************************************************
void Beep(char time)
//void Beep(void)
{
// char count;
for(count=0;count<0xFF;count++)
{
Beeper=1;
DelayUs(time);
// DelayUs(100);
Beeper=0;
DelayUs(time);
// DelayUs(100);
}
}
//******************* END OF Beep

//**********************************************************************
//RunGame - Will possibly run a game of scroll a message or something
//**********************************************************************
void RunGame(void)
{
ScrollMessage(0," Sorry No Game!! ");
DisplayData();
}

//******************* END OF RunGame

//**********************************************************************
//putch - Prints a single character to the LCD
//**********************************************************************
void putch(char c)
{
char str[2];
str[0]=c;
str[1]=0;
lcd_puts(str);
}
//******************* END OF putch


//**********************************************************************
//ScrollMessage
//**********************************************************************

void ScrollMessage(unsigned char row,const char Message[])
{
char TempS[21];
unsigned int MHead=0,Done=0;//,count;
if(row >1) row=1;
row=row*40;
while(Done==0)
{
for(count=0;count<20;count++)
{
TempS[count]=Message[MHead+count];
if(Message[MHead+count+1]==0) Done=1;
}
MHead++;
lcd_goto(row);
lcd_puts(TempS);
DelayMs(SCROLLDELAY);
}
}

//******************* END OF ScrollMessage

//**********************************************************************
//
//**********************************************************************

//******************* END OF


//**********************************************************************
//
//**********************************************************************

//******************* END OF

OK thats huge.

Have a go at converting it yourself.
Im here if you get stuck.

Remember to use hardware and software macros where applicable as it will save you a lot of time.

echase: It's not as hard as it sounds to do in Flowcode. The beginnings of a menu system or at least using a screen to enter characters based on button presses is covered in the example tutorial files which are installed under the flowcode directory.

I can't remember the exact tutorial numbers but it's the ones based on telephone number entry with a 16x2 LCD module.

I might have a look at a simple menu in a moment as it's raining outside so my firework tests are currently on hold. It's not nice when they get soggy!

Regards

Nick.W

My menu will not be as large as that one. So even a cut down (concept) translation of it into Flowcode would be useful thanks.

I am OK with writing to the LCD. My current flawed menu programme has an Interrupt on 4 bits of Port B to read the switches and a macro that returns one of 4 variables at value =1 depending on which button is pressed.

Where I get stuck is

1) Getting into a loop where it’s always waiting for a button to be pressed
2) How long do you wait before deciding a button is not going to be pressed and so move onto next step.
3) Reacting to multiple button presses, like lots of Up presses to scroll through the menu. My macro returns a value =1 for the first press so repressing it does nothing. Could clear the values to zero after say 1 sec delay.

Would stress that my 4 switches are on 4 different input lines. Not a row and column matrix like above C example.