| ffd4b35c |
1 | # Assemble with gas |
| 2 | # --register-prefix-optional --bitwise-or |
| 3 | |
| 4 | .macro ldarg arg, stacksz, reg |
| 5 | move.l (4 + \arg * 4 + \stacksz)(%sp), \reg |
| 6 | .endm |
| 7 | |
| 8 | .global burn10 /* u16 val */ |
| 9 | burn10: |
| 10 | ldarg 0, 0, d0 |
| 11 | subq.l #1, d0 |
| 12 | 0: |
| 13 | dbra d0, 0b |
| 14 | rts |
| 15 | |
| a385208c |
16 | .global write16_x16 /* u32 a, u16 count, u16 d */ |
| 17 | write16_x16: |
| 18 | ldarg 0, 0, a0 |
| 19 | ldarg 2, 0, d0 |
| 20 | move.w d0, d1 |
| 21 | swap d0 |
| 22 | move.w d1, d0 |
| 23 | ldarg 1, 0, d1 |
| 24 | subq.l #1, d1 |
| 25 | 0: |
| 26 | move.l d0, (a0) |
| 27 | move.l d0, (a0) |
| 28 | move.l d0, (a0) |
| 29 | move.l d0, (a0) |
| 30 | move.l d0, (a0) |
| 31 | move.l d0, (a0) |
| 32 | move.l d0, (a0) |
| 33 | move.l d0, (a0) |
| 34 | dbra d1, 0b |
| 35 | rts |
| 36 | |
| 37 | # read single phase from controller |
| 38 | # d0 - result |
| 39 | # destroys d1,d2 |
| 40 | .global get_input |
| 41 | get_input: |
| 42 | move.b #0x40,(0xa10003) |
| 43 | moveq.l #0,d0 |
| 44 | nop |
| 45 | nop |
| 46 | move.b (0xa10003),d1 |
| 47 | move.b #0x00,(0xa10003) |
| 48 | andi.w #0x3f,d1 /* 00CB RLDU */ |
| 49 | nop |
| 50 | move.b (0xa10003),d0 |
| 51 | lsl.b #2,d0 |
| 52 | andi.w #0xc0,d0 /* SA00 0000 */ |
| 53 | or.b d1,d0 |
| 54 | eor.b #0xff,d0 |
| 55 | .if 0 |
| 56 | swap d7 |
| 57 | move.w d7,d1 |
| 58 | eor.w d0,d1 /* changed btns */ |
| 59 | move.w d0,d7 /* old val */ |
| 60 | swap d7 |
| 61 | and.w d0,d1 /* what changed now */ |
| 62 | .endif |
| 63 | rts |
| 64 | |
| 65 | .global do_vcnt_vb |
| 66 | do_vcnt_vb: |
| 67 | movem.l d2-d7/a2, -(sp) |
| 68 | movea.l #0xc00007, a0 |
| 69 | movea.l #0xc00008, a1 |
| 70 | movea.l #0xff0000, a2 |
| 71 | moveq.l #0, d4 /* d4 = count */ |
| 72 | moveq.l #0, d5 /* d5 = vcnt_expect */ |
| 73 | /* d6 = old */ |
| 74 | move.l #1<<(3+16), d7 /* d7 = SR_VB */ |
| 75 | 0: |
| 76 | btst #3, (a0) |
| 77 | beq 0b /* not blanking */ |
| 78 | 0: |
| 79 | btst #3, (a0) |
| 80 | bne 0b /* blanking */ |
| 81 | |
| 82 | addq.l #1, a0 |
| 83 | 0: |
| 84 | tst.b (a0) |
| 85 | bne 0b /* not line 0 */ |
| 86 | |
| 87 | subq.l #2, a0 |
| 88 | move.l (a0), d6 |
| 89 | move.l d6, (a2)+ /* d0 = old */ |
| 90 | ### |
| 91 | 0: |
| 92 | move.b (a1), d2 /* 8 d2 = vcnt */ |
| 93 | cmp.b (a1), d2 /* 8 reread for corruption */ |
| 94 | bne 0b /* 10 on changing vcounter? */ |
| 95 | cmp.b d2, d5 /* 4 vcnt == vcnt_expect? */ |
| 96 | beq 0b /* 10 */ |
| 97 | move.l (a0), d0 /* 12 */ |
| 98 | tst.b d2 /* 4 */ |
| 99 | beq 3f |
| 100 | 1: |
| 101 | addq.l #1, d4 /* count++ */ |
| 102 | addq.l #1, d5 |
| 103 | cmp.b d2, d5 |
| 104 | bne 2f /* vcnt == vcnt_expect + 1 */ |
| 105 | move.l d0, d1 |
| 106 | eor.l d6, d1 |
| 107 | and.l d7, d1 /* (old ^ val) & vb */ |
| 108 | bne 2f |
| 109 | move.l d0, d6 /* old = val */ |
| 110 | bra 0b |
| 111 | |
| 112 | 2: /* vcnt jump or vb change */ |
| 113 | move.l d6, (a2)+ /* *ram++ = old */ |
| 114 | move.l d0, (a2)+ /* *ram++ = val */ |
| 115 | move.b d2, d5 /* vcnt_expect = vcnt */ |
| 116 | move.l d0, d6 /* old = val */ |
| 117 | bra 0b |
| 118 | |
| 119 | 3: /* vcnt == 0 */ |
| 120 | move.l d0, d1 |
| 121 | and.l d7, d1 |
| 122 | bne 1b /* still in VB */ |
| 123 | |
| 124 | move.l d0, (a2)+ /* *ram++ = val */ |
| 125 | move.l d4, (a2)+ /* *ram++ = count */ |
| 126 | |
| 127 | movem.l (sp)+, d2-d7/a2 |
| 128 | rts |
| 129 | |
| ffd4b35c |
130 | # vim:filetype=asmM68k:ts=4:sw=4:expandtab |
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