Mercurial > hg > Members > kono > nitros9-code
annotate level1/modules/dw4write.asm @ 2918:ada61f1951b7
dalpha: Use cmds/makefile from d64 port
The only difference was the duplicate dmode in a commands list.
| author | Tormod Volden <debian.tormod@gmail.com> |
|---|---|
| date | Fri, 17 Jan 2014 22:46:19 +0100 |
| parents | 28ed72477814 |
| children |
| rev | line source |
|---|---|
|
2898
28ed72477814
Dummy merge of default branch into lwtools
Tormod Volden <debian.tormod@gmail.com>
parents:
2741
diff
changeset
|
1 IFEQ H6309-1 |
| 2576 | 2 |
| 2574 | 3 ******************************************************* |
| 4 * | |
| 2576 | 5 * DWWrite - 6309 native Turbo Edition 115k / 230k |
| 6 * Send a packet to the DriveWire server. | |
| 7 * Serial data format: 8-N-2 | |
| 8 * | |
| 9 * Entry: | |
| 10 * X = address of the data to be sent | |
| 11 * Y = number of bytes to send | |
| 12 * | |
| 13 * Exit: | |
| 14 * X = address of last byte sent + 1 | |
| 15 * Y = 0 | |
| 16 * All others preserved | |
| 17 * | |
| 18 BBOUT equ $FF20 ; bit banger output port | |
| 19 | |
| 20 DWWrite pshs u,d,cc ; preserve registers | |
| 21 orcc #$50 ; mask interrupts | |
| 22 ldu #BBOUT ; point U to output port | |
| 23 aim #$F7,3,u ; disable sound output | |
| 24 | |
| 25 * Wait for serial input line to become idle | |
| 26 wait1 lda 2,u ; sample input | |
| 27 ldb #$80 ; setup ACCB as a shift counter | |
| 28 wait2 eora 2,u ; look for changing input | |
| 29 lsra ; shift 'changed' bit into Carry | |
| 30 lda 2,u ; sample input | |
| 31 rorb ; rotate 'changed' bit into ACCB | |
| 32 bcc wait2 ; loop for 8 samples | |
| 33 bne wait1 ; try again if changes seen in the input | |
| 34 | |
| 35 * Byte transmitter loop | |
| 36 incb ; ACCB = 1 (start bit / byte incrementor) | |
| 37 txByte lda ,x ; get data byte | |
| 38 stb ,u ; send start bit | |
| 39 asla ; move bit 0 into position | |
| 40 abx ; increment data ptr | |
| 41 sta ,u++ ; bit 0 | |
| 42 rora | |
| 43 nop | |
| 44 sta ,--u ; bit 1 | |
| 45 lsra | |
| 46 sta ,u++ ; bit 2 | |
| 47 lsra | |
| 48 nop | |
| 49 sta ,--u ; bit 3 | |
| 50 lsra | |
| 51 nop | |
| 52 sta ,u++ ; bit 4 | |
| 53 lsra | |
| 54 nop | |
| 55 sta ,--u ; bit 5 | |
| 56 lsra | |
| 57 sta ,u++ ; bit 6 | |
| 58 lsra | |
| 59 aslb ; ACCB = 2 (stop bit) | |
| 60 sta ,--u ; bit 7 | |
| 61 leau ,u | |
| 62 stb ,u ; send stop bit | |
| 63 lsrb ; ACCB = 1 (start bit / byte incrementor) | |
| 64 leay -1,y ; decrement counter | |
| 65 bne txByte ; loop if more bytes to send | |
| 66 | |
| 67 puls cc,d,u,pc ; restore registers and return | |
| 68 | |
| 69 ELSE | |
| 70 | |
| 71 ******************************************************* | |
| 72 * | |
| 73 * DWWrite - 6809 Turbo Edition 115k / 230k | |
| 2574 | 74 * Send a packet to the DriveWire server. |
| 75 * Serial data format: 8-N-2 | |
| 76 * | |
| 77 * Entry: | |
| 78 * X = address of the data to be sent | |
| 79 * Y = number of bytes to send | |
| 80 * | |
| 81 * Exit: | |
| 82 * X = address of last byte sent + 1 | |
| 83 * Y = 0 | |
| 84 * All others preserved | |
| 85 * | |
| 86 *BBOUT equ $FF20 ; bit banger output port | |
| 87 | |
| 88 DWWrite pshs u,d,cc ; preserve registers | |
| 89 orcc #$50 ; mask interrupts | |
| 90 ldu #BBOUT ; point U to output port | |
| 91 lda 3,u ; read PIA 1-B control register | |
| 92 anda #$F7 ; clear sound enable bit | |
| 93 sta 3,u ; disable sound output | |
| 94 | |
| 95 * Wait for serial input line to become idle | |
| 96 wait1 lda 2,u ; sample input | |
| 97 ldb #$80 ; setup ACCB as a shift counter | |
| 98 wait2 eora 2,u ; look for changing input | |
| 99 lsra ; shift 'changed' bit into Carry | |
| 100 lda 2,u ; sample input | |
| 101 rorb ; rotate 'changed' bit into ACCB | |
| 102 bcc wait2 ; loop for 8 samples | |
| 103 bne wait1 ; try again if changes seen in the input | |
| 104 | |
| 105 * Byte transmitter loop | |
| 106 ldb #2 | |
| 107 lda ,x ; retrieve first byte from buffer | |
| 108 txByte decb ; ACCB = 1 (start bit / byte incrementor) | |
| 109 abx ; increment data ptr | |
| 110 stb ,u ; send start bit | |
| 111 asla ; move bit 0 into position | |
| 112 nop | |
| 113 sta ,u ; bit 0 | |
| 114 rora | |
| 115 sta ,u+ ; bit 1 | |
| 116 lsra | |
| 117 sta -1,u ; bit 2 | |
| 118 lsra | |
| 119 sta ,-u ; bit 3 | |
| 120 lsra | |
| 121 incb ; ACCB = 2 (stop bit) | |
| 122 sta ,u ; bit 4 | |
| 123 lsra | |
| 124 sta ,u+ ; bit 5 | |
| 125 lsra | |
| 126 sta -1,u ; bit 6 | |
| 127 lsra | |
| 128 sta ,-u ; bit 7 | |
| 129 lda ,x ; fetch next byte | |
| 130 stb ,u ; send stop bit | |
| 131 leay -1,y ; decrement counter | |
| 132 bne txByte ; loop if more bytes to send | |
| 133 | |
| 134 puls cc,d,u,pc ; restore registers and return | |
| 135 | |
| 2576 | 136 ENDC |