GCBASIC / Discussion / Contributors: 4 I/O LCD_NO

There are many, many queries on this forum about why LCD_NO_RW seems to cause LCD display corruption.
Having spent many hours coding the AVR (arduino Mega 2560) using GCBasic a solution has emerged.
There is a popular 5 pin LCD Arduino shield that requires LCD_NO_RW to be defined.
A secondary problem is that port direction setting for Ports H,I,J,K,L etc does not work. The Arduino LCD shield needs some pins from Port H to work.
As expected the LCD display was corrupting horribly.
This has been solved with the code submitted below.
The modification is in the 4 I/O line subroutines as they are most popular.
Many project developers choose to save 5 pins by defining LCD_NO_RW and LCD_IO 4
The problem lies in the fact that without the nice, crisp LCD_RW control line the LCD controller needs to allowed
sufficient time to process the data/cursor control nibbles being sent.
Having examined the datasheet for the popular Hitachi HD44780 and checking the time delays in the lcd.h library it became clear that the time delays are out by a factor of 15.
In the code below the changes have been commented.
There is a problem with copying 'codified' text in some browsers - all the code is copied without line breaks.
Simply right-click anywhere on the code and select 'View Page source'.
The code will appear in a new window towards the bottom in a useable format.
Just backup your original LCD.h file , create a new LCD.h file and paste this code into it.
'    Liquid Crystal Display routines for Great Cow BASIC
'    Copyright (C) 2006 - 2009 Hugh Considine, Stefano Bonomi
'    This library is free software; you can redistribute it and/or
'    modify it under the terms of the GNU Lesser General Public
'    License as published by the Free Software Foundation; either
'    version 2.1 of the License, or (at your option) any later version.
'    This library is distributed in the hope that it will be useful,
'    but WITHOUT ANY WARRANTY; without even the implied warranty of
'    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
'    Lesser General Public License for more details.
'    You should have received a copy of the GNU Lesser General Public
'    License along with this library; if not, write to the Free Software
'    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
'********************************************************************************
'IMPORTANT:
'THIS FILE IS ESSENTIAL FOR SOME OF THE COMMANDS IN GCBASIC. DO NOT ALTER THIS FILE
'UNLESS YOU KNOW WHAT YOU ARE DOING. CHANGING THIS FILE COULD RENDER SOME GCBASIC
'COMMANDS UNUSABLE!
'********************************************************************************
'Credits:
' 4 and 8 bit routines  Hugh Considine
' 2 bit routines    Stefano Bonomi
' Testing       Stefano Adami
' Arduino MOD added 10/05/2013.  PORTH not handled correctly in GCbasic so LCD corrupting
' Added code to ensure display is properly initalized after watchdog reset
' FOR LCD_NO_RW CHANGE DELAY TIMES IN "LCD NORMAL BYTE WRITE" AND "LCD CURSOR" ROUTINES TO 700 uS
#startup InitLCD
'I/O Ports
#define LCD_IO 4 'Number of pins used for LCD data bus (2, 4 or 8)
'Sub used to write to LCD. Can be altered to allow custom LCD interfaces.
#define LCDWriteByte LCDNormalWriteByte
#define LCDReadByte LCDNormalReadByte
#define LCD_DB SysLCDTemp.0 'Data bit. Used in 2-bit mode
#define LCD_CB SysLCDTemp.0 'Clock bit. Used in 2-bit mode
#define LCD_DATA_PORT SysLCDTemp 'Port to connect to LCD data bus. Used in 8-bit mode
#define LCD_DB4 SysLCDTemp.0 'Output bit to interface with LCD data bus. Used in 4-bit mode
#define LCD_DB5 SysLCDTemp.0 'Output bit to interface with LCD data bus. Used in 4-bit mode
#define LCD_DB6 SysLCDTemp.0 'Output bit to interface with LCD data bus. Used in 4-bit mode
#define LCD_DB7 SysLCDTemp.0 'Output bit to interface with LCD data bus. Used in 4-bit mode
#define LCD_RS SysLCDTemp.1 'Output bit to control LCD Register Select. Used as variable by 2-bit mode, and as a pin in 4 and 8 bit mode. DO NOT CHANGE FOR 2-BIT MODE.
#define LCD_RW SysLCDTemp.0 'Output bit to select read/write
#define LCD_Enable SysLCDTemp.0 'Output bit to enable/disable LCD
#define LCD_RSTemp SysLCDTemp.2
'Misc Settings
#define LCD_Write_Delay 50 10us
#define FLASH 2
'#define LCD_NO_RW
'Lines for bar graph
#define LCD_BAR_EMPTY b'00010001'
#define LCD_BAR_FULL 255
Sub PUT (In LCDPutLine, In LCDPutColumn, In LCDChar)
    LOCATE LCDPutLine, LCDPutColumn
    Set LCD_RS on
    LCDWriteByte(LCDChar)
End Sub
'GET not available in 2-bit mode
Function GET (LCDPutLine, LCDPutColumn)
    Locate LCDPutLine, LCDPutColumn
    Set LCD_RS on
    GET = LCDReadByte
End Function
'LCDColumn is 0 to screen width-1, LCDLine is 0 to screen height-1
Sub LOCATE (In LCDLine, In LCDColumn)
    Set LCD_RS Off
    If LCDLine > 1 Then
        LCDLine = LCDLine - 2
        LCDColumn = LCDColumn + 20
    End If

    LCDWriteByte(0x80 or 0x40 * LCDLine + LCDColumn)
    Wait 5 10us
End Sub
Sub CLS
    SET LCD_RS OFF

    'Clear screen
    LCDWriteByte (b'00000001')
    Wait 2 ms

    'Move to start of visible DDRAM
    LCDWriteByte(0x80)
    Wait 10 10us
End Sub
'Compatibility with older programs
#define LCDInt Print
#define LCDWord Print
'String output
sub Print (PrintData As String)
    'PrintLen = LEN(PrintData$)
    PrintLen = PrintData(0)

    If PrintLen = 0 Then Exit Sub
    Set LCD_RS On

    'Write Data
    For SysPrintTemp = 1 To PrintLen
        LCDWriteByte PrintData(SysPrintTemp)
    Next

End Sub
Sub Print (In LCDValue)

    LCDValueTemp = 0
    Set LCD_RS On

    IF LCDValue >= 100 Then
        LCDValueTemp = LCDValue / 100
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
    End If

    If LCDValueTemp > 0  Then     '**new code because or command doesn't work on AVR
        LCDValueTemp = LCDValue / 10
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
    End If
    goto skip_or_thingy

    If  LCDValue >= 10 Then  '**new or command doesn't work on AVR
        LCDValueTemp = LCDValue / 10
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
    End If
    skip_or_thingy:
    LCDWriteByte (LCDValue + 48)
End Sub
Sub Print (In LCDValue As Word)
    Dim SysCalcTempX As Word
    Set LCD_RS On
    LCDValueTemp = 0

    If LCDValue >= 10000 then 
        LCDValueTemp = LCDValue / 10000 [word]
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
        Goto LCDPrintWord1000
    End If
    If LCDValue >= 1000 then
        LCDPrintWord1000:
        LCDValueTemp = LCDValue / 1000 [word]
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
        Goto LCDPrintWord100
    End If
    If LCDValue >= 100 then
        LCDPrintWord100:
        LCDValueTemp = LCDValue / 100 [word]
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
        Goto LCDPrintWord10
    End If
    If LCDValue >= 10 then
        LCDPrintWord10:
        LCDValueTemp = LCDValue / 10 [word]
        LCDValue = SysCalcTempX
        LCDWriteByte(LCDValueTemp + 48)
    End If
    LCDWriteByte (LCDValue + 48)
End Sub
Sub Print (In LCDValueInt As Integer)
    Dim LCDValue As Word

    'If sign bit is on, print - sign and then negate
    If LCDValueInt.15 = On Then
        LCDWriteChar("-")
        LCDValue = -LCDValueInt

    'Sign bit off, so just copy value
    Else
        LCDValue = LCDValueInt
    End If

    'Use Print(word) to display value
    Print LCDValue
End Sub
sub LCDHex(In LCDValue)
    LCDValueTemp = 0
    Set LCD_RS On

    IF LCDValue >= 0x10 then
        LCDValueTemp = LCDValue / 0x10
        LCDValue = SysCalcTempX
        LCDHexValueTemp = LCDValueTemp
        if LCDHexValueTemp > 9 then LCDHexValueTemp = LCDHexValueTemp + 7
        LCDWriteByte(LCDHexValueTemp + 48)
    end if

    LCDHexValueTemp = LCDValue
    if LCDHexValueTemp > 9 then LCDHexValueTemp = LCDHexValueTemp + 7
    LCDWriteByte (LCDHexValueTemp + 48)

end sub
sub LCDWriteChar(In LCDChar)
    set LCD_RS on
    LCDWriteByte(LCDChar)
end sub
function LCDReady
    #IFDEF LCD_NO_RW
        Wait 10 ms
        LCDReady = TRUE
        exit function
    #ENDIF

    #IFNDEF LCD_NO_RW
        #IFDEF LCD_IO 2
            LCDReady = TRUE
            exit function
        #ENDIF

        #IFDEF LCD_IO 4,8
            LCDReady = FALSE
            LCD_RSTemp = LCD_RS

            SET LCD_RW ON
            SET LCD_RS OFF

            Wait 5 10us
            SET LCD_Enable ON
            Wait 5 10us

            #IFDEF LCD_IO 4
                dir LCD_DB7 IN       
                                        '** new code
                #IFDEF AVR THEN         'added this poke routine as port H is not handeled properly on Arduino
                    tweak = peek(0x101) 'changes porth.4 to input while preserving other port bit directions
                    tweak.4 = 0         'this is specifically for the Arduino to work with an LCD
                    poke (0x101,tweak) ' b'01101000' set port H pin directions (DDRH register) manually *NEED to POKE this value. compiler use of DIR  doesn't work
                       ' use portH 3,4,5,6 as output for LCD .  1= output,  0 = input
                       ' porth.3 = LCD bit 6
                       ' porth.4 = LCD bit 7
                       ' porth.5 = LCD RS
                       ' porth.6 = LCD enable
                       ' portb.4 = LCD backlight ("0" = off)
                #ENDIF

                if LCD_DB7 OFF THEN LCDReady = TRUE
            #ENDIF
            #IFDEF LCD_IO 8
                dir LCD_DATA_PORT In
                if LCD_DATA_PORT.7 OFF THEN LCDReady = TRUE
            #ENDIF
            SET LCD_Enable OFF
            wait 25 10us
            LCD_RS = LCD_RSTemp
        #ENDIF
    #ENDIF
end function
sub LCDNormalWriteByte(In LCDByte)         '*** USE LONGER DELAY SETTINGS IF LCD_NO_RW IS DEFINED

    #IFNDEF LCD_NO_RW
        #IFDEF LCD_IO 4,8
            wait until LCDReady
            set LCD_RW OFF 'Write mode
        #ENDIF
    #ENDIF

    #IFDEF LCD_IO 2
        LCD2_NIBBLEOUT Swap4(LCDByte)   'Swap byte; Most significant NIBBLE sent first 
        LCD2_NIBBLEOUT LCDByte          'Less Significant NIBBLE output
    #ENDIF

    #IFDEF LCD_IO 4
        'Set pins to output
        DIR LCD_DB4 OUT
        DIR LCD_DB5 OUT
        DIR LCD_DB6 OUT
        DIR LCD_DB7 OUT     
                                 
        #IFDEF AVR                       'added this routine as port H is not handled properly on AVR 2560/arduino. Specifically added for Arduino LCD 5 button shield
        tweak = peek(0x101)              'peek into register for porth pin direction
        tweak.3=1                        'copy register byte to variable and modify bits 3 and 4 to be outputs. preserve direction of other pins
        tweak.4=1                        'poke new byte back into porth pin direction register
        poke (0x101,tweak) ' b'01111000' set port H pin directions (DDRH register) manually *NEED to POKE this value. compiler use of DIR  doesn't work
                       ' use portH 3,4,5,6 as output for LCD .  1= output,  0 = input
                       ' porth.3 = LCD bit 6
                       ' porth.4 = LCD bit 7
                       ' porth.5 = LCD RS
                       ' porth.6 = LCD enable
                       ' portb.4 = LCD backlight ("0" = off)

        #ENDIF

        'Write upper nibble to output pins
        set LCD_DB4 OFF
        set LCD_DB5 OFF
        set LCD_DB6 OFF
        set LCD_DB7 OFF
        if LCDByte.7 ON THEN SET LCD_DB7 ON
        if LCDByte.6 ON THEN SET LCD_DB6 ON
        if LCDByte.5 ON THEN SET LCD_DB5 ON
        if LCDByte.4 ON THEN SET LCD_DB4 ON

        'Pulse enable pin            '*** new code  added this IFDEF to lengthen delay
        #IFDEF LCD_NO_RW             'when LCD_NO_RW is defined. otherwise display corrupts
        Wait 70 10us                 '300 uS is too fast so use 700 us
        PULSEOUT LCD_Enable, 70 10us
        Wait  70 10us        
        #ENDIF

        #IFNDEF LCD_NO_RW          'IF LCD_RW pin is in use then use short delays
        Wait 5 10us                 'i.e  LCD_NO_RW not defined
        PULSEOUT LCD_Enable, 5 10us
        Wait 5 10us
        #ENDIF

        'Write lower nibble to output pins
        set LCD_DB4 OFF
        set LCD_DB5 OFF
        set LCD_DB6 OFF
        set LCD_DB7 OFF
        if LCDByte.3 ON THEN SET LCD_DB7 ON
        if LCDByte.2 ON THEN SET LCD_DB6 ON
        if LCDByte.1 ON THEN SET LCD_DB5 ON
        if LCDByte.0 ON THEN SET LCD_DB4 ON

        'Pulse enable pin            '*** new code  added this IFDEF to lengthen delay
        #IFDEF LCD_NO_RW             'when LCD_NO_RW is defined. otherwise display corrupts
        Wait 70 10us                 '300 uS is too fast so use 700 us
        PULSEOUT LCD_Enable, 70 10us
        Wait  70 10us            
        #ENDIF

        #IFNDEF LCD_NO_RW          'IF LCD_RW pin is in use then use short delays
        Wait 5 10us                'i.e  LCD_NO_RW not defined
        PULSEOUT LCD_Enable, 5 10us
        Wait 5 10us
        #ENDIF

        'Set data pins low again
        SET LCD_DB7 OFF
        SET LCD_DB6 OFF
        SET LCD_DB5 OFF
        SET LCD_DB4 OFF
    #ENDIF

    #IFDEF LCD_IO 8
        'Set data port to output, and write a value to it
        DIR LCD_DATA_PORT out
        LCD_DATA_PORT = LCDByte

        'Pulse enable pin
        Wait 5 10us
        PULSEOUT LCD_Enable, 5 10us
        Wait 5 10us

        'Clear port again, in case it is shared with something else
        LCD_DATA_PORT = 0
    #ENDIF

end sub
SUB LCD2_NIBBLEOUT (In LCD2BYTE)
 'Set Data and Clock bits off
 SET LCD_DB OFF
 SET LCD_CB OFF
 'Clear Shift Register With six 0s prior to loading
 FOR LCDTemp = 1 TO 6   
  SET LCD_CB ON  ' STROBE
  SET LCD_CB OFF ' ======
 NEXT
 SET LCD_DB ON  ' First bit out to Shift register, always 1 for E gate
 SET LCD_CB ON  ' STROBE
 SET LCD_CB OFF ' ======
 IF LCD_RS OFF THEN SET LCD_DB OFF ' Second bit out equal to R/S
 SET LCD_CB ON  ' STROBE
 SET LCD_CB OFF ' ======                                    
 '4 bits Data out to Shift register, starting from Nibble most significant bit
 FOR LCDTemp = 1 to 4
  SET LCD_DB OFF
  IF LCD2Byte.3 ON THEN SET LCD_DB ON
  SET LCD_CB ON
  SET LCD_CB OFF
  ROTATE LCD2Byte LEFT
 NEXT
SET LCD_DB ON               ' Last pulse for Nibble output. Not for Shift register
WAIT 1 MS               ' Put E pin on LCD to one through an AND operation 
SET LCD_DB OFF              ' with the first bit outputted (E)
END SUB
function LCDNormalReadByte
    #IFDEF LCD_NO_RW
        LCDReadByte = 0
        Exit Function
    #ENDIF

    #IFNDEF LCD_NO_RW

        set LCD_RW ON 'Read mode
        LCDReadByte = 0

        #IFDEF LCD_IO 4
            'Set pins to input
            DIR LCD_DB4 IN
            DIR LCD_DB5 IN
            DIR LCD_DB6 IN
            DIR LCD_DB7 IN

                '** new code
                #IFDEF AVR THEN         'added this poke routine as port H is not handeled properly on Arduino
                    tweak = peek(0x101) 'changes porth.4 to input while preserving other port bit directions
                    tweak.4 = 0         'this is specifically for the Arduino to work with an LCD
                    poke (0x101,tweak) ' b'01101000' set port H pin directions (DDRH register) manually *NEED to POKE this value. compiler use of DIR  doesn't work
                       ' use portH 3,4,5,6 as output for LCD .  1= output,  0 = input
                       ' porth.3 = LCD bit 6
                       ' porth.4 = LCD bit 7
                       ' porth.5 = LCD RS
                       ' porth.6 = LCD enable
                       ' portb.4 = LCD backlight ("0" = off)
                #ENDIF

            'Read upper nibble from input pins
            SET LCD_Enable ON
            Wait LCD_Write_Delay
            if LCD_DB7 ON then SET LCDReadByte.7 ON
            if LCD_DB6 ON THEN SET LCDReadByte.6 ON
            if LCD_DB5 ON then SET LCDReadByte.5 ON
            if LCD_DB4 ON THEN SET LCDReadByte.4 ON
            SET LCD_Enable OFF
            Wait 2 10us

            'Read lower nibble from input pins
            SET LCD_Enable ON
            Wait LCD_Write_Delay
            if LCD_DB7 ON then SET LCDReadByte.3 ON
            if LCD_DB6 ON THEN SET LCDReadByte.2 ON
            if LCD_DB5 ON then SET LCDReadByte.1 ON
            if LCD_DB4 ON THEN SET LCDReadByte.0 ON
            SET LCD_Enable OFF
            Wait 2 10us
        #ENDIF

        #IFDEF LCD_IO 8
            DIR LCD_DATA_PORT 255
            SET LCD_Enable ON
            Wait LCD_Write_Delay
            LCDReadByte = LCD_DATA_PORT
            SET LCD_Enable OFF
            Wait 2 10us
        #ENDIF
    #ENDIF
end function
sub InitLCD  'copied from source forge to ensure lcd is initialized properly after watchdog reset
    #IFDEF LCD_IO 2
        DIR LCD_DB OUT
        DIR LCD_CB OUT
        SET LCD_DB OFF
        SET LCD_CB OFF
        Wait 35 ms
        SET LCD_RS OFF
        LCD2_NIBBLEOUT 0X03
        Wait 5 ms
        LCD2_NIBBLEOUT 0X03
        Wait 1 MS
        LCD2_NIBBLEOUT 0X03
        Wait 1 MS
        LCD2_NIBBLEOUT 0X02
        Wait 1 MS
        LCDWriteByte 0x28
        Wait 1 MS
        LCDWriteByte 0x08
        Wait 1 MS
        LCDWriteByte 0x01
        Wait 5 MS
        LCDWriteByte 0x06
        WAIT 1 MS
        LCDWriteByte 0x0C
        WAIT 1 MS
    #ENDIF

    #IFDEF LCD_IO 4,8
        DIR LCD_DB4 OUT
        DIR LCD_DB5 OUT
        DIR LCD_DB6 OUT
        DIR LCD_DB7 OUT
        
        #IFDEF AVR                       'added this routine as port H is not handled properly on AVR 2560/arduino. Specifically added for Arduino LCD 5 button shield
        tweak = peek(0x101)              'peek into register for porth pin direction
        tweak.3=1                        'copy register byte to variable and modify bits 3 and 4 to be outputs. preserve direction of other pins
        tweak.4=1                        'poke new byte back into porth pin direction register
        poke (0x101,tweak) ' b'01111000' set port H pin directions (DDRH register) manually *NEED to POKE this value. compiler use of DIR  doesn't work
                       ' use portH 3,4,5,6 as output for LCD .  1= output,  0 = input
                       ' porth.3 = LCD bit 6
                       ' porth.4 = LCD bit 7
                       ' porth.5 = LCD RS
                       ' porth.6 = LCD enable
                       ' portb.4 = LCD backlight ("0" = off)

        #ENDIF

        DIR LCD_RS OUT
        #IFNDEF LCD_NO_RW
            DIR LCD_RW OUT
        #ENDIF
        DIR LCD_Enable OUT
        SET LCD_RS OFF
        SET LCD_RW OFF
        SET LCD_Enable OFF
        SET LCD_DB4 OFF
        SET LCD_DB5 OFF
        SET LCD_DB6 OFF
        SET LCD_DB7 OFF

        ' wait for more than 15ms after power up
        Wait 35 ms

        ' Function set (Interface is 8 bits long.)
        SET LCD_DB4 ON
        SET LCD_DB5 ON

        PulseOut LCD_Enable, LCD_Write_Delay
        Wait 6 ms

        ' Function set (Interface is 8 bits long.)
        SET LCD_DB4 ON
        SET LCD_DB5 ON

        PulseOut LCD_Enable, LCD_Write_Delay
        Wait 6 ms

        ' Function set (Interface is 8 bits long.)
        SET LCD_DB4 ON
        SET LCD_DB5 ON

        PulseOut LCD_Enable, LCD_Write_Delay
        Wait 6 ms
        #IFDEF LCD_IO 8
            LCDWriteByte(b'00111000') 
        #ENDIF
        #IFDEF LCD_IO 4
            ' set IO mode to 4bit 
            SET LCD_DB4 OFF
            SET LCD_DB5 ON
            PulseOut LCD_Enable, LCD_Write_Delay

            SET LCD_RS OFF
            LCDWriteByte(b'00101000') ' function set: display 2 lines 
            wait LCD_Write_Delay
        #ENDIF
        LCDWriteByte(b'00001000') ' 0x08 : display off
        wait LCD_Write_Delay

        LCDWriteByte(b'00000001') ' 0x01 : display clear
        wait LCD_Write_Delay
        LCDWriteByte(b'00000110') ' xx06 : set entry mode  (increment by 1, no shift)  
        wait LCD_Write_Delay

        LCDWriteByte(b'00001100') ' 0x0C : display on /cursor off control
        wait LCD_Write_Delay
    #endif

end sub
sub LCDCursor(In LCDCRSR)
    'Can be ON, FLASH or OFF
    Set LCD_RW OFF
    LCDTemp = 12 '0 or 12
    If LCDCRSR = ON Then LCDTemp = 14 '2 or 12
    If LCDCRSR = FLASH Then LCDTemp = 15 '3 or 12
    'If LCDCRSR = OFF Then LCDTemp = 0 or 12
    LCDWriteByte(LCDTemp) '(LCDTemp or 12)

    #IFDEF LCD_NO_RW    'use longer delay
    Wait  70 10us '300 uS is too fast so use 700 us
    #ENDIF

    #IFNDEF LCD_NO_RW
    Wait 5 10us
    #ENDIF

end sub
'Create a custom character in CGRAM
sub LCDCreateChar (In LCDCharLoc, LCDCharData())

    'Store old location
    #IFDEF LCD_IO 4,8
        Set LCD_RS Off
        LCDLoc = LCDReadByte
        Set LCDLoc.7 On
    #ENDIF

    'Select location
    Set LCD_RS Off
    LCDWriteByte (64 + LCDCharLoc * 8)
    wait 5 10us

    'Write char
    Set LCD_RS On
    For LCDTemp = 1 to 8
        LCDWriteByte LCDCharData(LCDTemp)
        wait 5 10us
    Next

    'Restore location
    #IFDEF LCD_IO 2
        set LCD_RS off
        LCDWriteByte(0x80)
        wait 5 10us
    #ENDIF
    #IFDEF LCD_IO 4,8
        Set LCD_RS Off
        LCDWriteByte (LCDLoc)
        wait 5 10us
    #ENDIF
end sub
'Create a graph character in CGRAM
Sub LCDCreateGraph(In LCDCharLoc, In LCDValue)
    'Store old location
    #IFDEF LCD_IO 4,8
        Set LCD_RS Off
        LCDLoc = LCDReadByte
        Set LCDLoc.7 On
    #ENDIF

    'Select location
    Set LCD_RS Off
    LCDWriteByte (64 + LCDCharLoc * 8)
    wait 5 10us

    'Write char for graph
    Set LCD_RS On
    For LCDTemp = 8 to 1
        If LCDTemp > LCDValue Then
            LCDWriteByte LCD_BAR_EMPTY
        Else
            LCDWriteByte LCD_BAR_FULL
        End If
        wait 5 10us
    Next

    'Restore location
    #IFDEF LCD_IO 2
        set LCD_RS off
        LCDWriteByte(0x80)
        wait 5 10us
    #ENDIF
    #IFDEF LCD_IO 4,8
        Set LCD_RS Off
        LCDWriteByte (LCDLoc)
        wait 5 10us
    #ENDIF

End Sub
4 I/O LCD_NO_RW display corruption fixed AVR

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4 I/O LCD_NO_RW display corruption fixed AVR

4 I/O LCD_NO_RW display corruption fixed AVR

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4 I/O LCD_NO_RW display corruption fixed AVR
