' LED scrolling text demo.

'Library Load "matrix.lib"
'Library Load "text.lib"

Save "text.bas"

' Picomite
Const m7219_clk = 4 ' GP2
Const m7219_cs  = 7 ' GP5
Const m7219_tx  = 5 ' GP3
Const m7219_rx  = 6 ' GP4

SetPin m7219_cs, Dout
SetPin m7219_rx, m7219_tx, m7219_clk, SPI

Pin(m7219_cs) = 1 ' Active low, so initially set high

'Cls
m7219_init(8,32)
'm7219_init(8,8)
'matrix_fill()
m7219_draw()
text_init()
SetTick 50, m7219_draw
s$ = MM.CmdLine$
If Len(s$) = 0 Then Line Input "Message: ", s$
text_scroll(s$)
End

' **********
' matrix.lib
' **********

' LED matrix manipulation library.

' Makes use of a global matrix(8) created by calling matrix_init().
' Elements 0-7 are the 8-bit pattern for the matrix columns.

Sub matrix_init()
 Local i
 For i = 1 To 8 : SetPin i, dout : Next i
 For i = 11 To 18 : SetPin i, dout : Next i
 matrix_nc = 8
 Dim matrix(matrix_nc - 1) ' All elements initalised to 0
 matrix_r = 0
End Sub

Sub matrix_clear()
 Local i
 For i = 0 To matrix_nc - 1 : matrix(i) = 0 : Next i
End Sub

Sub matrix_fill()
 Local i
 For i = 0 To matrix_nc - 1 : matrix(i) = &hFF : Next i
End Sub

Function matrix_get(x, y)
 Local x2, y2
 x2 = x + (y \ 8) * matrix_w
 y2 = y Mod 8
 matrix_get = (matrix(x2) And 2^y2) > 0
End Function

Sub matrix_set(x, y, z)
 Local x2, y2
 x2 = x + (y \ 8) * matrix_w
 y2 = y Mod 8
 matrix(x2) = matrix(x2) And (&hFF Xor 2^y2) Or (z * 2^y2)
End Sub

Sub matrix_left()
 Local i
 For i = 0 To matrix_nc - 2 : matrix(i) = matrix(i + 1) : Next i
 matrix(matrix_nc - 1) = 0
End Sub

' Updates scanline/row 'matrix_r'.
'
' Assumes that a HIGH is required on the row & column to light the LED.
' If a LOW is required on the row then use the commented out values in the
' calls to Port().
'
' This routine needs to be fast (it is called every 2ms) hence the
' unrolled loop used to calculate 'x'.
'
' A much faster implementation is possible if matrix data is stored by
' rows instead of columns, i.e.
'
'   Port(1, 8, 11, 8) = matrix(matrix_r) Or 2^(matrix_r + 8)
Sub matrix_draw()
 Local m, x
 m = 2^matrix_r
 x = ((matrix(0) And m) > 0) Or 2 * ((matrix(1) And m) > 0)
 x = x Or 4  * ((matrix(2) And m) > 0) Or 8   * ((matrix(3) And m) > 0)
 x = x Or 16 * ((matrix(4) And m) > 0) Or 32  * ((matrix(5) And m) > 0)
 x = x Or 64 * ((matrix(6) And m) > 0) Or 128 * ((matrix(7) And m) > 0)
 Port(1, 8, 11, 8) = 0 ' &hFF00
 Port(1, 8, 11, 8) = x Or 2^(matrix_r + 8) ' &hFF00 - 2^(matrix_r + 8)
 matrix_r = (matrix_r + 1) Mod 8
End Sub

Sub m7219_init(w, h)
 Local i
 If w Mod 8 <> 0 Then Error "Invalid number of columns: " + Str$(w)
 If w Mod 8 <> 0 Then Error "Invalid number of rows: " + Str$(h)
 matrix_nc = w * (h \ 8)
 matrix_h = h
 matrix_w = w
 Dim matrix(matrix_nc - 1) ' all elements initialised to 0

 SPI Open 3000000, 0, 16

 For i = 0 To matrix_nc \ 8 - 1
   m7219_write(&h0900, i) ' BCD DECODE ALL DIGITS
   m7219_write(&h0A00, i) ' BRIGHTNESS (0-15)
   m7219_write(&h0B07, i) ' 8 COLUMNS
   m7219_write(&h0F00, i) ' TESTS OFF
   m7219_write(&h0C01, i) ' OPERATING MODE (i.e. NOT SHUTDOWN MODE)
 Next i

 m7219_draw() ' Clears the matrix - is this necessary?
End Sub

Sub m7219_draw()
 Local c
 For c = 0 To matrix_nc - 1
   m7219_write((1 + c Mod 8) * 256 + matrix(c), c \ 8)
 Next c
End Sub

Sub m7219_write(x, idx)
 Local i
'  SPI Open 3000000, 3, 16
 Pin(m7219_cs) = 0
 For i = matrix_nc \ 8 - 1 To 0 Step -1
'    null = SPI(m7219_rx, m7219_tx, m7219_clk, x * (i = idx), H, 3, 16)
   null = SPI(x * (i = idx))
 Next i
 Pin(m7219_cs) = 1
End Sub

Sub digits_init()
 Local i, x
 Dim digits(9, 7) ' 10 digits, 8 columns per character

 ' Each DATA line represents dot-patterns for the 8-columns
 ' (left to right) msb=bottom dot, lsb=top dot

 Data &h7E, &hFF, &hFF, &hC3, &hC3, &hFF, &hFF, &h7E ' 0
 Data &h00, &h00, &h04, &h06, &hFF, &hFF, &hFF, &h00 ' 1
 Data &hE6, &hE7, &hF7, &hD3, &hDB, &hCF, &hCF, &hC6 ' 2
 Data &hDB, &hDB, &hDB, &hDB, &hDB, &hFF, &hFF, &h66 ' 3
 Data &h1F, &h1F, &h1F, &h18, &hFF, &hFF, &hFF, &h18 ' 4
 Data &h5F, &hDF, &hDF, &hDB, &hDB, &hFB, &hFB, &h73 ' 5
 Data &h7E, &hFF, &hFF, &hDB, &hDB, &hFB, &hFB, &h72 ' 6
 Data &h03, &h03, &hE3, &hF3, &hFB, &h1F, &h0F, &h07 ' 7
 Data &h66, &hFF, &hFF, &hDB, &hDB, &hFF, &hFF, &h66 ' 8
 Data &h4E, &hDF, &hDF, &hDB, &hDB, &hFF, &hFF, &h7E ' 9

 For i = 0 To 9
   For x = 0 To 7
     Read digits(i, x)
   Next x
 Next i
End Sub

' **********
' text.lib
' **********

' LED font display library.

' Makes use of a global font4x6() array created by calling text_init().

Sub text_init()
 Local end, height, i, j, s$, start, x, width

 Open "tt4x6.fnt" For Input As #1

 Input #1, height, width, start, end
 If height <> 6 Then Error
 If width <> 4  Then Error
 If start <> 20 Then Error
 If end <> 126  Then Error

 ' This is actually more storage than is required because it allocates
 ' 4 bytes per glyph and we only need 3.
 Dim font4x6(end - start)

 For i = 0 To (end - start) ' Iterate over glyphs
   For j = 0 To 5 Step 2 ' Iterate over rows, 2 at a time
     x = 0
     Line Input #1, s$
     If Len(s$) <> width Then Error
     If Peek(Var s$, 1) > 32 Then x = x Or &b00000001
     If Peek(Var s$, 2) > 32 Then x = x Or &b00000010
     If Peek(Var s$, 3) > 32 Then x = x Or &b00000100
     If Peek(Var s$, 4) > 32 Then x = x Or &b00001000
     Line Input #1, s$
     If Len(s$) <> width Then Error
     If Peek(Var s$, 1) > 32 Then x = x Or &b00010000
     If Peek(Var s$, 2) > 32 Then x = x Or &b00100000
     If Peek(Var s$, 3) > 32 Then x = x Or &b01000000
     If Peek(Var s$, 4) > 32 Then x = x Or &b10000000
     Poke Var font4x6(0), i * 3 + j \ 2, x
   Next j
 Next i
 Close #1
End Sub

Sub text_scroll(s$)
 Local c, ch, i

 cmd = 0
 For i = 1 To Len(s$)
'    Print "x";
   ch = Peek(Var s$, i)
   For c = 0 To 3
'      Print "y";
     ' Poor man's proportional spacing.
     If c = 0 And ch = 105 Then c = 1
     If c = 2 And ch = 105 Then c = 3
     If c = 1 And ch = 32  Then c = 4
'      Print "a";
     text_blit(Peek(Var s$, i), c)
'      Print "b";
     Pause 150
'      Print "c";
     matrix_left()
   Next c
   If cmd <> 0 Then i = Len(s$)
 Next i
'  Print "leaving"
 For i = 1 To matrix_nc : Pause 100 : matrix_left() : Next i
End Sub

' Copies column 'c' of glyph 'a' to the last column of the matrix.
Sub text_blit(a, c)
 Local i, p, s, z

 p = 1
 s = (a - 20) * 3
 For i = s To s + 2
   z = Peek(Var font4x6(0), i)
   matrix_set(matrix_nc - 1, p, (z And 2^c) > 0)
   p = p + 1
   matrix_set(matrix_nc - 1, p, (z And 2^(c+4)) > 0)
   p = p + 1
 Next i
End Sub