Minimal NTSC Template for Propeller -- NON Interlace (262 lines)

ntsc.spin

CON
    _CLKMODE = RCSlow     ' Start prop in RCSlow mode internal crystal

PUB main

    clkset(%01101000,  12_000_000)          ' Set internal oscillator to RCFast and set PLL to start
    waitcnt(cnt+120_000)                    ' wait approx 10ms at 12mhz for PLL to 'warm up'

    clkset( %01101111, 80_000_000 )         ' 80MHz (5MHz PLLx16)  
    coginit( COGID, @cogstart, @cogstart )


DAT
            org         0
cogstart
            mov         vcfg, ivcfg         ' Sets up the parameters for video generation
            mov         ctra, ictra         ' internal PLL mode, PLLA = 16 * colorburst frequency
            mov         frqa, ifrqa         ' 2 * colorburst frequency 
            mov         dira, idira         ' Sets pin directions

mainloop
            mov         numline, #9         ' 9 lines of vsync
vsync0
            cmp         numline, #6     wz  ' lines 4,5,6 serration pulses
    if_nz   cmp         numline, #5     wz  ' lines 1,2,3 / 7,8,9 equalizing pulses
    if_nz   cmp         numline, #4     wz  ' 
            
            mov         count, #2           ' 2 pulses per line
:half
    if_nz   mov         VSCL, vscleqal      ' equalizing pulse (short)
    if_z    mov         VSCL, vsclselo      ' serration pulse (long)
            waitvid     sync, #0            ' -40 IRE
    if_nz   mov         VSCL, vscleqhi      ' equalizing pulse (long)
    if_z    mov         VSCL, vsclsync      ' serration pulse (short)
            waitvid     sync, blank         ' 0 IRE

            djnz        count, #:half
            djnz        numline, #vsync0

            mov         numline, #12        ' 12 blank lines
blank0
            mov         VSCL, vsclsync
            waitvid     sync, #0            ' -40 IRE
            mov         VSCL, vsclblnk
            waitvid     sync, blank         ' 0 IRE
            djnz        numline, #blank0


            mov         numline, #241       ' 241 lines of active video
active
            mov         VSCL, vsclsync      ' horizontal sync (0H)
            waitvid     sync, #0            ' -40 IRE
            mov         VSCL, vscls2cb      ' 5.3us 0H to burst
            waitvid     sync, blank            
            mov         VSCL, vsclbrst      ' 9 cycles of colorburst
            waitvid     sync, burst
            mov         VSCL, vsclbp        ' backporch 9.2us OH to active video
            waitvid     sync, blank
            
'-----------------------------------------------------------------------------------------------
'   VISIBLE SCAN LINE START
'-----------------------------------------------------------------------------------------------
            movd        :loop, #colors      ' initialize pointer
            mov         count, #(17*6+2)/4  ' number of WAITVIDs
            mov         VSCL, vsclactv      ' PLLA per pixel, 4 pixels per frame
:loop
            waitvid     colors, #%%3210
            add         :loop, d1
            djnz        count, #:loop
'-----------------------------------------------------------------------------------------------
'   VISIBLE SCAN LINE END
'-----------------------------------------------------------------------------------------------
            mov         VSCL, vsclfp        ' front porch 1.5us
            waitvid     sync, blank
            
            djnz        numline, #active
            jmp         #mainloop


'-----------------------------------------------------------------------------------------------
'   CONFIG DATA
'-----------------------------------------------------------------------------------------------
ivcfg                   long    %0_11_1_0_1_000_00000000000_001_0_01110000      ' demoboard
ictra                   long    %0_00001_110_00000000_000000_000_000000         ' NTSC
ifrqa                   long    $16E8_BA2F                                      ' (7,159,090.9Hz/80MHz)<<32 NTSC demoboard & Hydra 
idira                   long    $0000_7000                                      ' demoboard

sync                    LONG    $8A0200                                         ' %%0 = -40 IRE, %%1 = 0 IRE, %%2 = burst
blank                   LONG    %%1111_1111_1111_1111                           ' 16 pixels color 1
burst                   LONG    %%2222_2222_2222_2222                           ' 16 pixels color 1

vscleqal                long    1<<12+135               ' NTSC sync/2
vsclsync                long    1<<12+269               ' NTSC sync = 4.7us
vsclblnk                long    1<<12+3371              ' NTSC H-sync
vsclselo                long    1<<12+1551              ' NTSC H/2-sync
vscleqhi                long    1<<12+1685              ' NTSC H/2-sync/2
vscls2cb                long    1<<12+304-269           ' NTSC sync to colorburst
vsclbrst                long    16<<12+16*9           ' NTSC 16 PLLA per cycle, 9 cycles of colorburst
vsclbp                  long    1<<12+(527-304-16*9)+213' NTSC back porch + overscan (213)
vsclactv                long    25<<12+25*4             ' NTSC 25 PLLA per pixel, 4 pixels per frame
vsclfp                  long    1<<12+214+86            ' NTSC overscan (214) + front porch

numline                 long    $0
count                   long    $0
d1                      long    1<<9

colors
                        byte    $02                            ' LONG padding
                        byte    $07, $06, $05, $04, $03, $02   ' white to black (6 levels)
                        BYTE    $0B, $0C, $0D, $0E, $8F, $88   ' 16 hues, 6 shades/hue
                        BYTE    $1B, $1C, $1D, $1E, $9F, $98
                        BYTE    $2B, $2C, $2D, $2E, $AF, $A0
                        BYTE    $3B, $3C, $3D, $3E, $BF, $B8
                        BYTE    $4B, $4C, $4D, $4E, $CF, $C8
                        BYTE    $5B, $5C, $5D, $5E, $DF, $D8
                        BYTE    $6B, $6C, $6D, $6E, $EF, $E8
                        BYTE    $7B, $7C, $7D, $7E, $FF, $F8
                        BYTE    $8B, $8C, $8D, $8E, $0F, $08
                        BYTE    $9B, $9C, $9D, $9E, $1F, $18
                        BYTE    $AB, $AC, $AD, $AE, $2F, $28
                        BYTE    $BB, $BC, $BD, $BE, $3F, $38
                        BYTE    $CB, $CC, $CD, $CE, $4F, $48
                        BYTE    $DB, $DC, $DD, $DE, $5F, $58
                        BYTE    $EB, $EC, $ED, $EE, $6F, $68
                        BYTE    $FB, $FC, $FD, $FE, $7F, $78

                        byte    $02                            ' LONG padding