MY FIRST scrolling 8X8 LED

[skimask]

http://www.picbasic.co.uk/forum/show...ght=copystring
Simple macro to copy a string from the mainline of code into a byte array of STRING.
Then you can dribble thru that byte array, pull out whatever you need...

And if you do a search for 'printstr' (or in my case printstr2), you'll find another macro that is actually set up for either an LCD or the serial port but could be easily modified to drive 8x8 LEDs...which for all practical purposes are just like a graphic LCD as far as showing items.

Take a look at them. If you've never messed with macro's, this is a perfect place to try them out and get to know them...
Obviously, you can most likely do this without the macro's and just use lookup tables and such. I think you'll be much happier with the copystring/printstr/tables-in-flash concept.

[earltyso]

Skimask,
I will do some looking into the macro coding,
Looks like it does the job, can you show me where I would insert my string of characters?

I would really like to use lookup tables for this project as I have a grasp on them.
Right now I am just really stumped on how to use arrays with lookup tables to get a full 8x8 matrice of values to the screen one column at a time...???? then of coarse how to shift that entire matrice left or right while fetching the next array to feed into the screen.

[skimask]

Skimask,
I will do some looking into the macro coding,
Looks like it does the job, can you show me where I would insert my string of characters?

I would really like to use lookup tables for this project as I have a grasp on them.
Right now I am just really stumped on how to use arrays with lookup tables to get a full 8x8 matrice of values to the screen one column at a time...???? then of coarse how to shift that entire matrice left or right while fetching the next array to feed into the screen.

If the PIC you're using has internal eeprom, put the table there (the table is actually a matrix of what each character will look like when displayed on the LEDs, almost like what you've got in your first post). In fact, for testing, you could probably use the tables that are already in some of that code (5x7 font) and expand them later on. If the PIC doesn't have internal eeprom, you could still put the table into the code space (search 'making code space your playground').

Shifting - tables - Rather than trying to figure out how to shift an entire column or whatever, I think you have to worry more about getting the thing to work in the first place just displaying single characters at will. Once that's finished, the code for shifting one column at a time should fall into place.

Just as a for instance, say you want to display an O ( a big square O because it's easy) on an 8x8 LED. First byte (first column) is $ff, all 1's, 2nd-7th byte (columns) are %10000001 ($81), top and bottom LEDs on, last byte (column) is just like the first.
When you display a character, you give it a code, such as using ASCII as I did (just not all of it). A big, capital O is ASCII value $4F (79 decimal).
So now, say you've got a table already setup with all of the values plugged in. There's 127 ASCII characters (ok, not all of them displayable according to the ASCII standard, but you can use those non-displayable characters for 'special' characters).
127 characters times 8 columns for each = 1,016 bytes total, call it 1K.
You want to display character 'O', as in capital O. The ASCII value is $4F, so your loop would start at offset $4F times the number of bytes for each character (8), $4F x 8 = $278 (632 decimal), and run for 7 additional columns past that, for 8 columns total. After each read from memory for the byte values, you put that out to the LED matrix.

If you get that working, it'll be a piece of cake to figure out how to do scrolling...

[earltyso]

I like the idea of storing the table to eeprom.
Here is what I have come up with. So far I have built up A,B,C,D in my library and they are scrolling just fine by shifting 8 times to the left. Now what I want to do is have the letters scroll TOGETHER so that the letters merge into a sentence without 8 columns of dead space between letters.
I will be trying to figure this out over the weekend. I still need to optimize my table but at its a start.

DEFINE OSC 12

'ADCON1 = 4 'this sets ANO, AN1, AN3 ON
ADCON1 = 7' ALL DIGITAL
TRISB = 0
TRISC = 0
SINK   VAR PORTB 'ROWS
SOURCE VAR PORTC 'COLUMNS
x var byte
y var byte
z var byte
A VAR BYTE
B VAR BYTE
S VAR BYTE
STP VAR BYTE
'CHAR var byte[8]

SOURCEA VAR WORD
SOURCEB VAR WORD
SOURCEC VAR WORD
SOURCED VAR WORD
SOURCEE VAR WORD
SOURCEF VAR WORD
SOURCEG VAR WORD
SOURCEH VAR WORD

LETTERS VAR BYTE ' VARIABLE TO HOLD CHARACTERS IN F/N LOOP
CHAR var byte[26]' ARRAY VARIABLE NAMED CHAR 26 ELEMENTS

'* * * * * * LOAD ARRAY WITH STRING VALUE * * * * * * * * * * *

CHAR[0]= "A"
CHAR[1]= "B"
CHAR[2]= "C"
CHAR[3]= "D"
CHAR[4]= "E"
CHAR[5]= "F"
CHAR[6]= "G"
CHAR[7]= "H"
CHAR[8]= "I"
CHAR[9]= "J"
CHAR[10]="K"
CHAR[11]="L"
CHAR[12]="M"
CHAR[13]="N"
CHAR[14]="O"
CHAR[15]="P"
CHAR[16]="Q"
CHAR[17]="R"
CHAR[18]="S"
CHAR[19]="T"
CHAR[20]="U"
CHAR[21]="V"
CHAR[22]="W"
CHAR[23]="X"
CHAR[24]="Y"
CHAR[25]="Z"

MAIN2:
for x = 0 to 10
lookup x, [0,1,2,3,3,3,2,2,1,1,0], LETTERS      'EQUIVALENT TO a,b,c,d,d,d,c,c,b,b,a
                                    'NOT WORKING OBVIOUSLY
'FOR LETTERS = 0 TO 2               'LOOKUP ASCII CHARACTERS STORED IN MATRICE ARRAY ,A,B,C
    'FOR STP = 0 TO 1               'SCROLL CHARACTER OFF PAGE NOT SURE HOW TO IMPLEMENT
        'FOR S = 0 TO 1             'MULTIPLEX SCREEN PAUSING ~10ms EACH SCAN
		  GoSub display	            'FETCH THE 8 ROWS 
        'NEXT S 
    'NEXT STP 
    
NEXT X		
GOTO MAIN2

display:             'A   'B   'C   'D   'E  
        Lookup LETTERS, [$0, $0, $0, $0], SOURCEA
        PORTC = SOURCEA
        PORTB = %11111110
        PAUSE 1
        Lookup LETTERS, [%01000010, %01111110, %01111110,%01111110], SOURCEB
        PORTC = SOURCEB
        PORTB = %11111101
        PAUSE 1
        Lookup LETTERS, [%01000010, %01000010, %00000010,%01000010], SOURCEC
        PORTC = SOURCEC
        PORTB = %11111011
        PAUSE 1
        Lookup LETTERS, [%01111110,%01000010 , %00000010,%01000010], SOURCED
        PORTC = SOURCED
        PORTB = %11110111
        PAUSE 1
        Lookup LETTERS, [%01000010, %01000110, %00100010,%01100010], SOURCEE
        PORTC = SOURCEE
        PORTB = %11101111
        PAUSE 1                     
        Lookup LETTERS, [%00111100, %00111010, %00111100,%01011100], SOURCEF
        PORTC = SOURCEF
        PORTB = %11011111
        PAUSE 1
        Lookup LETTERS, [$0, %00000010, $0,%01000000], SOURCEG
        PORTC = SOURCEG
        PORTB = %10111111
        PAUSE 1
        Lookup LETTERS, [$0, %00000010, $0,%01000000], SOURCEH
        PORTC = SOURCEH
        PORTB = %01111111 
        PAUSE 1
        
FOR STP = 0 TO 7           'SCROLL MR. SMILEY OFF SCREEN
    FOR S = 0 TO 15        'SCAN SCREEN 21 TIMES (FAST) BETWEEN SCROLLING
        PAUSE 1
        PORTB = %11111110
        PORTC = SOURCEA >>STP
        PAUSE 1
        PORTB = %11111101
        PORTC = SOURCEB >>STP
        PAUSE 1
        PORTB = %11111011
        PORTC = SOURCEC >>STP
        PAUSE 1
        PORTB = %11110111
        PORTC = SOURCED >>STP
        PAUSE 1
        PORTB = %11101111
        PORTC = SOURCEE >>STP
        PAUSE 1
        PORTB = %11011111
        PORTC = SOURCEF >>STP
        PAUSE 1
        PORTB = %10111111
        PORTC = SOURCEG >>STP
        PAUSE 1
        PORTB = %01111111
        PORTC = SOURCEH >>STP
    NEXT S
NEXT STP
'GOTO MAIN
        
RETURN

[skimask]

Instead of this:

'* * * * * * LOAD ARRAY WITH STRING VALUE * * * * * * * * * * *
CHAR[0]= "A"
CHAR[1]= "B"
CHAR[2]= "C"
CHAR[3]= "D"
CHAR[4]= "E"
CHAR[5]= "F"
CHAR[6]= "G"
CHAR[7]= "H"
CHAR[8]= "I"
CHAR[9]= "J"
CHAR[10]="K"
CHAR[11]="L"
CHAR[12]="M"
CHAR[13]="N"
CHAR[14]="O"
CHAR[15]="P"
CHAR[16]="Q"
CHAR[17]="R"
CHAR[18]="S"
CHAR[19]="T"
CHAR[20]="U"
CHAR[21]="V"
CHAR[22]="W"
CHAR[23]="X"
CHAR[24]="Y"
CHAR[25]="Z"

Try this:

For temp = "A" to "Z" : CHAR[ temp - "A" ] = temp : Next temp

Easier to type, uses less memory, and so on...

Another idea for you...

Put the complete message into an array of bytes, the whole message, columns and all, not just the ASCII representation of each character (i.e. each character will use up 8 bytes in the array).
Then, when displaying the message, (is the matrix actually 8x8? or are there really more 8x8 chunks involved?), shift the array by one column, pause, redisplay it...

[sayzer]

Instead of this:

'* * * * * * LOAD ARRAY WITH STRING VALUE * * * * * * * * * * *
CHAR[0]= "A"
CHAR[1]= "B"
CHAR[2]= "C"
CHAR[3]= "D"
CHAR[4]= "E"
CHAR[5]= "F"
CHAR[6]= "G"
CHAR[7]= "H"
CHAR[8]= "I"
CHAR[9]= "J"
CHAR[10]="K"
CHAR[11]="L"
CHAR[12]="M"
CHAR[13]="N"
CHAR[14]="O"
CHAR[15]="P"
CHAR[16]="Q"
CHAR[17]="R"
CHAR[18]="S"
CHAR[19]="T"
CHAR[20]="U"
CHAR[21]="V"
CHAR[22]="W"
CHAR[23]="X"
CHAR[24]="Y"
CHAR[25]="Z"

Try this:

For temp = "A" to "Z" : CHAR[ temp ] = temp : Next temp

Easier to type, uses less memory, and so on...

Another idea for you...

Put the complete message into an array of bytes, the whole message, columns and all, not just the ASCII representation of each character (i.e. each character will use up 8 bytes in the array).
Then, when displaying the message, (is the matrix actually 8x8? or are there really more 8x8 chunks involved?), shift the array by one column, pause, redisplay it...

Ski,


About the array loop and indexing it;

When Temp = "A", how will "CHAR[ temp ] = temp" work?

Where will "A" go? CHAR[65] ?


What about CHAR[Temp-65] = Temp ?


---------------------

Note: I just realized that my edit updated after Ski posted!

[skimask]

Ski,

About the array loop and indexing it;

When Temp = "A", how will "CHAR[ temp ] = temp" work?

Where will "A" go?
CHAR[65] ?

Nothing personal, just want to know

DOH!!!
Char[ temp - "A" ]
That should be a bit better, ya think?

Note: I just saw that Sayzer had edited after I had posted