1 EESchema Schematic File Version 4 2 LIBS:AcornElectronMainboard-cache 3 EELAYER 26 0 4 EELAYER END 5 $Descr A4 8268 11693 portrait 6 encoding utf-8 7 Sheet 1 9 8 Title "Acorn Electron Mainboard" 9 Date "" 10 Rev "" 11 Comp "" 12 Comment1 "" 13 Comment2 "" 14 Comment3 "" 15 Comment4 "" 16 $EndDescr 17 $Comp 18 L AcornElectron:ULA12C021 IC1 19 U 1 1 61CC86CA 20 P 4300 4100 21 F 0 "IC1" H 4300 6750 50 0000 C CNN 22 F 1 "ULA12C021" H 4300 6650 50 0000 C CNN 23 F 2 "" H 4300 4100 50 0001 C CNN 24 F 3 "" H 4300 4100 50 0001 C CNN 25 1 4300 4100 26 1 0 0 -1 27 $EndComp 28 Text Label 2900 3900 2 50 ~ 0 29 A0 30 Text Label 2900 4300 2 50 ~ 0 31 A4 32 Text Label 2900 4400 2 50 ~ 0 33 A5 34 Text Label 2900 4500 2 50 ~ 0 35 A6 36 Text Label 2900 4600 2 50 ~ 0 37 A7 38 Text Label 2900 4700 2 50 ~ 0 39 A8 40 Text Label 2900 4800 2 50 ~ 0 41 A9 42 Text Label 2900 4900 2 50 ~ 0 43 A10 44 Text Label 2900 5000 2 50 ~ 0 45 A11 46 Text Label 2900 5100 2 50 ~ 0 47 A12 48 Text Label 2900 5200 2 50 ~ 0 49 A13 50 Text Label 2900 5300 2 50 ~ 0 51 A14 52 Text Label 2900 4000 2 50 ~ 0 53 A1 54 Text Label 2900 4100 2 50 ~ 0 55 A2 56 Text Label 2900 4200 2 50 ~ 0 57 A3 58 Text Label 2900 5400 2 50 ~ 0 59 A15 60 Wire Bus Line 61 1700 3800 2100 3800 62 Entry Wire Line 63 2100 3800 2200 3900 64 Entry Wire Line 65 2100 4000 2200 4100 66 Entry Wire Line 67 2100 4100 2200 4200 68 Entry Wire Line 69 2100 4200 2200 4300 70 Entry Wire Line 71 2100 4300 2200 4400 72 Entry Wire Line 73 2100 4400 2200 4500 74 Entry Wire Line 75 2100 4500 2200 4600 76 Entry Wire Line 77 2100 4600 2200 4700 78 Entry Wire Line 79 2100 4700 2200 4800 80 Entry Wire Line 81 2100 4800 2200 4900 82 Entry Wire Line 83 2100 4900 2200 5000 84 Entry Wire Line 85 2100 5000 2200 5100 86 Entry Wire Line 87 2100 5100 2200 5200 88 Entry Wire Line 89 2100 5200 2200 5300 90 Entry Wire Line 91 2100 5300 2200 5400 92 Entry Wire Line 93 2100 3900 2200 4000 94 Wire Wire Line 95 2200 3900 2900 3900 96 Wire Wire Line 97 2200 4000 2900 4000 98 Wire Wire Line 99 2200 4100 2900 4100 100 Wire Wire Line 101 2200 4200 2900 4200 102 Wire Wire Line 103 2200 4300 2900 4300 104 Wire Wire Line 105 2200 4400 2900 4400 106 Wire Wire Line 107 2200 4500 2900 4500 108 Wire Wire Line 109 2200 4600 2900 4600 110 Wire Wire Line 111 2200 4700 2900 4700 112 Wire Wire Line 113 2200 4800 2900 4800 114 Wire Wire Line 115 2200 4900 2900 4900 116 Wire Wire Line 117 2200 5000 2900 5000 118 Wire Wire Line 119 2200 5100 2900 5100 120 Wire Wire Line 121 2200 5200 2900 5200 122 Wire Wire Line 123 2200 5300 2900 5300 124 Entry Wire Line 125 2100 2300 2200 2400 126 Entry Wire Line 127 2100 2400 2200 2500 128 Entry Wire Line 129 2100 2500 2200 2600 130 Entry Wire Line 131 2100 2600 2200 2700 132 Entry Wire Line 133 2100 2700 2200 2800 134 Entry Wire Line 135 2100 2800 2200 2900 136 Entry Wire Line 137 2100 2900 2200 3000 138 Entry Wire Line 139 2100 3000 2200 3100 140 Wire Wire Line 141 2200 2400 2900 2400 142 Wire Wire Line 143 2200 2500 2900 2500 144 Wire Wire Line 145 2200 2600 2900 2600 146 Wire Wire Line 147 2200 2700 2900 2700 148 Wire Wire Line 149 2200 2800 2900 2800 150 Wire Wire Line 151 2200 2900 2900 2900 152 Wire Wire Line 153 2200 3000 2900 3000 154 Wire Wire Line 155 2200 3100 2900 3100 156 Text Label 2900 2400 2 50 ~ 0 157 RA0 158 Text Label 2900 2500 2 50 ~ 0 159 RA1 160 Text Label 2900 2600 2 50 ~ 0 161 RA2 162 Text Label 2900 2700 2 50 ~ 0 163 RA3 164 Text Label 2900 2800 2 50 ~ 0 165 RA4 166 Text Label 2900 2900 2 50 ~ 0 167 RA5 168 Text Label 2900 3000 2 50 ~ 0 169 RA6 170 Text Label 2900 3100 2 50 ~ 0 171 RA7 172 Wire Wire Line 173 2300 2100 2900 2100 174 Wire Wire Line 175 2500 2200 2900 2200 176 Text Label 2900 2100 2 50 ~ 0 177 ~WE 178 Text Label 2900 2200 2 50 ~ 0 179 ~RAS 180 Text Label 2900 2300 2 50 ~ 0 181 ~CAS 182 Wire Wire Line 183 2200 2000 2900 2000 184 Wire Wire Line 185 2900 1900 2200 1900 186 Wire Wire Line 187 2900 1800 2200 1800 188 Wire Wire Line 189 2900 1700 2200 1700 190 Entry Wire Line 191 2100 1600 2200 1700 192 Entry Wire Line 193 2100 1700 2200 1800 194 Entry Wire Line 195 2100 1800 2200 1900 196 Entry Wire Line 197 2100 1900 2200 2000 198 Text Label 2900 1700 2 50 ~ 0 199 RAM0 200 Text Label 2900 1800 2 50 ~ 0 201 RAM1 202 Text Label 2900 1900 2 50 ~ 0 203 RAM2 204 Text Label 2900 2000 2 50 ~ 0 205 RAM3 206 Text Label 2900 5500 2 50 ~ 0 207 D0 208 Text Label 2900 5600 2 50 ~ 0 209 D1 210 Text Label 2900 5700 2 50 ~ 0 211 D2 212 Text Label 2900 5800 2 50 ~ 0 213 D3 214 Text Label 2900 5900 2 50 ~ 0 215 D4 216 Text Label 2900 6000 2 50 ~ 0 217 D5 218 Text Label 2900 6100 2 50 ~ 0 219 D6 220 Text Label 2900 6200 2 50 ~ 0 221 D7 222 Wire Wire Line 223 2900 3800 2300 3800 224 Wire Wire Line 225 2300 3800 2300 3700 226 Entry Wire Line 227 2100 3100 2200 3200 228 Entry Wire Line 229 2100 3200 2200 3300 230 Entry Wire Line 231 2100 3300 2200 3400 232 Entry Wire Line 233 2100 3400 2200 3500 234 Wire Wire Line 235 2200 3200 2900 3200 236 Wire Wire Line 237 2200 3300 2900 3300 238 Wire Wire Line 239 2200 3400 2900 3400 240 Wire Wire Line 241 2200 3500 2900 3500 242 $Comp 243 L Connector_Generic:Conn_01x03 PL3 244 U 1 1 61CF9DF4 245 P 1400 8900 246 F 0 "PL3" H 1320 9217 50 0000 C CNN 247 F 1 "Power" H 1320 9126 50 0000 C CNN 248 F 2 "" H 1400 8900 50 0001 C CNN 249 F 3 "~" H 1400 8900 50 0001 C CNN 250 1 1400 8900 251 -1 0 0 -1 252 $EndComp 253 Text GLabel 3700 8800 2 50 Output ~ 0 254 5V 255 Wire Wire Line 256 1600 8800 2100 8800 257 Text GLabel 3700 9300 2 50 Output ~ 0 258 0V 259 Text GLabel 3700 9800 2 50 Output ~ 0 260 -5V 261 Wire Wire Line 262 1900 9300 2000 9300 263 Wire Wire Line 264 1800 9800 2000 9800 265 Text GLabel 3800 7100 3 50 Input ~ 0 266 0V 267 Wire Wire Line 268 3800 7100 3800 6900 269 Wire Wire Line 270 3800 6900 4000 6900 271 Wire Wire Line 272 4000 6900 4000 6750 273 Connection ~ 3800 6900 274 Wire Wire Line 275 3800 6900 3800 6750 276 Text GLabel 3600 700 1 50 Input ~ 0 277 5V 278 Wire Wire Line 279 3600 700 3600 800 280 $Comp 281 L Device:R R5 282 U 1 1 61F10DD6 283 P 3800 1050 284 F 0 "R5" H 3650 1100 50 0000 L CNN 285 F 1 "24R" H 3750 1000 50 0000 R CNN 286 F 2 "" V 3730 1050 50 0001 C CNN 287 F 3 "~" H 3800 1050 50 0001 C CNN 288 1 3800 1050 289 1 0 0 -1 290 $EndComp 291 $Comp 292 L Device:R R58 293 U 1 1 61F10E39 294 P 4000 1050 295 F 0 "R58" H 4050 1100 50 0000 L CNN 296 F 1 "24R" H 4050 1000 50 0000 L CNN 297 F 2 "" V 3930 1050 50 0001 C CNN 298 F 3 "~" H 4000 1050 50 0001 C CNN 299 1 4000 1050 300 1 0 0 -1 301 $EndComp 302 Wire Wire Line 303 3800 1550 3800 1350 304 Wire Wire Line 305 3800 900 3800 800 306 Wire Wire Line 307 3800 800 3600 800 308 Connection ~ 3600 800 309 Wire Wire Line 310 3600 800 3600 1550 311 Wire Wire Line 312 4000 800 3800 800 313 Connection ~ 3800 800 314 $Comp 315 L Device:C C27 316 U 1 1 61FBBBB4 317 P 3350 1250 318 F 0 "C27" H 3250 1300 50 0000 R CNN 319 F 1 "10??F/TANT" H 3250 1200 38 0000 R CNN 320 F 2 "" H 3388 1100 50 0001 C CNN 321 F 3 "~" H 3350 1250 50 0001 C CNN 322 1 3350 1250 323 1 0 0 -1 324 $EndComp 325 Wire Wire Line 326 3600 800 3350 800 327 Wire Wire Line 328 3350 800 3350 1100 329 Text GLabel 3250 1500 0 50 Input ~ 0 330 0V 331 Wire Wire Line 332 3250 1500 3350 1500 333 Wire Wire Line 334 3350 1500 3350 1400 335 $Comp 336 L Device:C Ax19 337 U 1 1 621AFB3A 338 P 2700 9050 339 F 0 "Ax19" H 2815 9096 50 0000 L CNN 340 F 1 "47nF" H 2815 9005 50 0000 L CNN 341 F 2 "" H 2738 8900 50 0001 C CNN 342 F 3 "~" H 2700 9050 50 0001 C CNN 343 1 2700 9050 344 1 0 0 -1 345 $EndComp 346 $Comp 347 L Device:C Ax1 348 U 1 1 62245E33 349 P 2600 9550 350 F 0 "Ax1" H 2715 9596 50 0000 L CNN 351 F 1 "47nF" H 2715 9505 50 0000 L CNN 352 F 2 "" H 2638 9400 50 0001 C CNN 353 F 3 "~" H 2600 9550 50 0001 C CNN 354 1 2600 9550 355 1 0 0 -1 356 $EndComp 357 $Comp 358 L Device:CP C1 359 U 1 1 62245FAE 360 P 2100 9050 361 F 0 "C1" H 2218 9096 50 0000 L CNN 362 F 1 "47??F/16V" H 2218 9005 38 0000 L CNN 363 F 2 "" H 2138 8900 50 0001 C CNN 364 F 3 "~" H 2100 9050 50 0001 C CNN 365 1 2100 9050 366 1 0 0 -1 367 $EndComp 368 $Comp 369 L Device:CP C2 370 U 1 1 62245FF4 371 P 2000 9550 372 F 0 "C2" H 2118 9596 50 0000 L CNN 373 F 1 "10??F/16V" H 2118 9505 38 0000 L CNN 374 F 2 "" H 2038 9400 50 0001 C CNN 375 F 3 "~" H 2000 9550 50 0001 C CNN 376 1 2000 9550 377 1 0 0 -1 378 $EndComp 379 Wire Wire Line 380 1900 9300 1900 8900 381 Wire Wire Line 382 1900 8900 1600 8900 383 Wire Wire Line 384 1800 9800 1800 9000 385 Wire Wire Line 386 2100 8900 2100 8800 387 Connection ~ 2100 8800 388 Wire Wire Line 389 2100 8800 2700 8800 390 Wire Wire Line 391 2000 9400 2000 9300 392 Connection ~ 2000 9300 393 Wire Wire Line 394 2000 9300 2100 9300 395 Wire Wire Line 396 2100 9200 2100 9300 397 Connection ~ 2100 9300 398 Wire Wire Line 399 2100 9300 2600 9300 400 Wire Wire Line 401 2000 9700 2000 9800 402 Connection ~ 2000 9800 403 Wire Wire Line 404 2000 9800 2600 9800 405 Wire Wire Line 406 2600 9800 2600 9700 407 Connection ~ 2600 9800 408 Wire Wire Line 409 2600 9400 2600 9300 410 Connection ~ 2600 9300 411 Wire Wire Line 412 2600 9300 2700 9300 413 Wire Wire Line 414 2700 9300 2700 9200 415 Connection ~ 2700 9300 416 Wire Wire Line 417 2700 8900 2700 8800 418 Connection ~ 2700 8800 419 $Comp 420 L Connector_Generic:Conn_01x02 PL4 421 U 1 1 627DA4FF 422 P 1400 10100 423 F 0 "PL4" H 1320 10317 50 0000 C CNN 424 F 1 "Power" H 1320 10226 50 0000 C CNN 425 F 2 "" H 1400 10100 50 0001 C CNN 426 F 3 "~" H 1400 10100 50 0001 C CNN 427 1 1400 10100 428 -1 0 0 -1 429 $EndComp 430 Wire Wire Line 431 3600 6750 3600 7400 432 Wire Wire Line 433 3600 7400 3500 7400 434 Text Label 1600 8800 0 50 ~ 0 435 5V 436 Text Label 1600 8900 0 50 ~ 0 437 0V 438 Wire Wire Line 439 1600 9000 1800 9000 440 Text Label 1600 9000 0 50 ~ 0 441 -5V 442 Text Label 1600 10100 0 50 ~ 0 443 RETURN 444 Text Label 1600 10200 0 50 ~ 0 445 18VAC 446 Wire Wire Line 447 4600 7600 4600 6750 448 $Sheet 449 S 2800 7800 700 300 450 U 61DF4BC2 451 F0 "Clocks" 50 452 F1 "clocks.sch" 50 453 $EndSheet 454 Text GLabel 3500 7600 0 50 Input ~ 0 455 CLOCK_16MHz 456 Text GLabel 3500 7400 0 50 Input ~ 0 457 CLOCK_16MHz_DIV_13 458 $Sheet 459 S 1200 1100 700 300 460 U 61D7EEE8 461 F0 "RAM" 50 462 F1 "RAM.sch" 50 463 $EndSheet 464 Wire Bus Line 465 2100 2300 1700 2300 466 Wire Bus Line 467 2100 1600 1700 1600 468 Text GLabel 1700 1600 0 50 BiDi ~ 0 469 RAM[0..3] 470 Text GLabel 1700 2300 0 50 Output ~ 0 471 RA[0..7] 472 $Sheet 473 S 5800 1300 700 300 474 U 624B50A6 475 F0 "Cassette" 50 476 F1 "cassette.sch" 50 477 $EndSheet 478 Text GLabel 5800 3600 2 50 Input ~ 0 479 CASSETTE_INPUT 480 Wire Wire Line 481 5600 3600 5800 3600 482 Text GLabel 5800 1800 2 50 Output ~ 0 483 CASSETTE_OUTPUT 484 Wire Wire Line 485 5600 1800 5800 1800 486 $Sheet 487 S 5800 4200 700 300 488 U 61E9B87F 489 F0 "Sound" 50 490 F1 "sound.sch" 50 491 $EndSheet 492 Text GLabel 5800 4700 2 50 Output ~ 0 493 SOUND_OUTPUT 494 Wire Wire Line 495 5600 4700 5800 4700 496 Text GLabel 2600 10100 2 50 UnSpc ~ 0 497 POWER_AC_RETURN 498 Text GLabel 2600 10200 2 50 UnSpc ~ 0 499 POWER_18VAC 500 Wire Wire Line 501 1600 10100 2100 10100 502 Wire Wire Line 503 1600 10200 2100 10200 504 Wire Wire Line 505 3500 7600 4600 7600 506 Text GLabel 1700 6400 0 50 Output ~ 0 507 PHI_OUT 508 $Sheet 509 S 1300 7800 700 300 510 U 61FB7D7E 511 F0 "Expansion" 50 512 F1 "expansion.sch" 50 513 $EndSheet 514 Text GLabel 1700 5400 0 50 BiDi ~ 0 515 D[0..7] 516 Wire Bus Line 517 1700 5400 2100 5400 518 Text GLabel 1700 3800 0 50 Input ~ 0 519 A[0..15] 520 Text GLabel 1700 6600 0 50 Input ~ 0 521 RnW 522 Text GLabel 2000 6500 0 50 Output ~ 0 523 ~IRQ 524 Text GLabel 2000 6300 0 50 Input ~ 0 525 ~NMI 526 Text GLabel 2700 3700 0 50 Input ~ 0 527 ~RST 528 $Sheet 529 S 1300 6800 700 300 530 U 61F2273C 531 F0 "CPU, ROM, keyboard" 50 532 F1 "CPU_ROM_KBD.sch" 50 533 $EndSheet 534 Text GLabel 1700 3100 0 50 Input ~ 0 535 KBD[0..3] 536 Wire Bus Line 537 1700 3100 2100 3100 538 Wire Wire Line 539 2700 3700 2900 3700 540 Entry Wire Line 541 2100 5400 2200 5500 542 Entry Wire Line 543 2100 5500 2200 5600 544 Entry Wire Line 545 2100 5600 2200 5700 546 Entry Wire Line 547 2100 5700 2200 5800 548 Entry Wire Line 549 2100 5800 2200 5900 550 Entry Wire Line 551 2100 5900 2200 6000 552 Entry Wire Line 553 2100 6000 2200 6100 554 Entry Wire Line 555 2100 6100 2200 6200 556 Wire Wire Line 557 2200 5500 2900 5500 558 Wire Wire Line 559 2200 5600 2900 5600 560 Wire Wire Line 561 2200 5700 2900 5700 562 Wire Wire Line 563 2200 5800 2900 5800 564 Wire Wire Line 565 2200 5900 2900 5900 566 Wire Wire Line 567 2200 6000 2900 6000 568 Wire Wire Line 569 2200 6100 2900 6100 570 Wire Wire Line 571 2200 6200 2900 6200 572 Text GLabel 1700 3600 0 50 Input ~ 0 573 CAPS_LOCK 574 Wire Wire Line 575 2200 5400 2900 5400 576 Text GLabel 1000 3700 0 50 Output ~ 0 577 ROM 578 Wire Wire Line 579 1700 3600 2900 3600 580 Wire Wire Line 581 2300 3700 1000 3700 582 Wire Wire Line 583 2000 6300 2900 6300 584 Wire Wire Line 585 2000 6500 2900 6500 586 Wire Wire Line 587 1700 6600 2900 6600 588 Wire Wire Line 589 1700 6400 2900 6400 590 $Sheet 591 S 4800 7800 700 300 592 U 61DB955D 593 F0 "Video" 50 594 F1 "video.sch" 50 595 $EndSheet 596 Wire Wire Line 597 6300 5500 6200 5500 598 Wire Wire Line 599 6300 5100 6200 5100 600 Wire Wire Line 601 5800 5100 5900 5100 602 Wire Wire Line 603 5800 5500 5900 5500 604 Wire Wire Line 605 5800 5300 5800 5100 606 Wire Wire Line 607 5800 5300 5800 5500 608 Connection ~ 5800 5300 609 Wire Wire Line 610 5600 5300 5800 5300 611 Text GLabel 6300 5500 2 50 Input ~ 0 612 0V 613 $Comp 614 L Device:C C9 615 U 1 1 621AE941 616 P 6050 5500 617 F 0 "C9" V 5798 5500 50 0000 C CNN 618 F 1 "1??F/35V/TANT" V 5889 5500 38 0000 C CNN 619 F 2 "" H 6088 5350 50 0001 C CNN 620 F 3 "~" H 6050 5500 50 0001 C CNN 621 1 6050 5500 622 0 1 1 0 623 $EndComp 624 Text GLabel 6300 5100 2 50 Input ~ 0 625 5V 626 $Comp 627 L Device:R R7 628 U 1 1 61FA16A2 629 P 6050 5100 630 F 0 "R7" V 5843 5100 50 0000 C CNN 631 F 1 "56000R" V 5934 5100 50 0000 C CNN 632 F 2 "" V 5980 5100 50 0001 C CNN 633 F 3 "~" H 6050 5100 50 0001 C CNN 634 1 6050 5100 635 0 1 1 0 636 $EndComp 637 Text GLabel 7100 6100 2 50 Output ~ 0 638 ~CSYNC 639 Text GLabel 7100 6700 2 50 Output ~ 0 640 BLUE 641 Text GLabel 7100 7300 2 50 Output ~ 0 642 GREEN 643 Text GLabel 7100 7900 2 50 Output ~ 0 644 RED 645 Wire Wire Line 646 5600 5700 6100 5700 647 Text GLabel 4900 7000 2 50 Output ~ 0 648 ~HS 649 Wire Wire Line 650 4800 6750 4800 7000 651 Wire Wire Line 652 4800 7000 4900 7000 653 Text GLabel 5800 2300 2 50 BiDi ~ 0 654 CASSETTE_RC 655 Text GLabel 5800 2600 2 50 Output ~ 0 656 CASSETTE_MOTOR 657 Wire Wire Line 658 5600 2300 5800 2300 659 Wire Wire Line 660 5600 2600 5800 2600 661 $Sheet 662 S 4800 7200 700 300 663 U 62411C42 664 F0 "UHF" 50 665 F1 "UHF.sch" 50 666 $EndSheet 667 Wire Wire Line 668 5600 6300 5800 6300 669 Wire Wire Line 670 5600 5900 6000 5900 671 Text Notes 5800 9150 0 50 ~ 0 672 Issue 6 boards tend to have\nIC19 (74LS08) fitted for\nsome kind of buffering\nof the video signals.\n\nLK7 is supposedly connected\nto +5V to ensure this. 673 $Comp 674 L 74xx:74LS08 IC19 675 U 1 1 61E3E3E3 676 P 6700 7300 677 F 0 "IC19" H 6700 7625 50 0000 C CNN 678 F 1 "74LS08" H 6700 7534 50 0000 C CNN 679 F 2 "" H 6700 7300 50 0001 C CNN 680 F 3 "http://www.ti.com/lit/gpn/sn74LS08" H 6700 7300 50 0001 C CNN 681 1 6700 7300 682 1 0 0 -1 683 $EndComp 684 $Comp 685 L 74xx:74LS08 IC19 686 U 2 1 61E3E49E 687 P 6700 7900 688 F 0 "IC19" H 6700 8225 50 0000 C CNN 689 F 1 "74LS08" H 6700 8134 50 0000 C CNN 690 F 2 "" H 6700 7900 50 0001 C CNN 691 F 3 "http://www.ti.com/lit/gpn/sn74LS08" H 6700 7900 50 0001 C CNN 692 2 6700 7900 693 1 0 0 -1 694 $EndComp 695 $Comp 696 L 74xx:74LS08 IC19 697 U 3 1 61E3E509 698 P 6700 6100 699 F 0 "IC19" H 6700 6425 50 0000 C CNN 700 F 1 "74LS08" H 6700 6334 50 0000 C CNN 701 F 2 "" H 6700 6100 50 0001 C CNN 702 F 3 "http://www.ti.com/lit/gpn/sn74LS08" H 6700 6100 50 0001 C CNN 703 3 6700 6100 704 1 0 0 -1 705 $EndComp 706 $Comp 707 L 74xx:74LS08 IC19 708 U 4 1 61E3E573 709 P 6700 6700 710 F 0 "IC19" H 6700 7025 50 0000 C CNN 711 F 1 "74LS08" H 6700 6934 50 0000 C CNN 712 F 2 "" H 6700 6700 50 0001 C CNN 713 F 3 "http://www.ti.com/lit/gpn/sn74LS08" H 6700 6700 50 0001 C CNN 714 4 6700 6700 715 1 0 0 -1 716 $EndComp 717 $Comp 718 L 74xx:74LS08 IC19 719 U 5 1 61E3E5E4 720 P 7200 8900 721 F 0 "IC19" H 7430 8946 50 0000 L CNN 722 F 1 "74LS08" H 7430 8855 50 0000 L CNN 723 F 2 "" H 7200 8900 50 0001 C CNN 724 F 3 "http://www.ti.com/lit/gpn/sn74LS08" H 7200 8900 50 0001 C CNN 725 5 7200 8900 726 1 0 0 -1 727 $EndComp 728 Wire Wire Line 729 5800 6300 5800 7800 730 Wire Wire Line 731 5800 7800 6400 7800 732 Wire Wire Line 733 5900 6100 5900 7200 734 Wire Wire Line 735 5900 7200 6400 7200 736 Wire Wire Line 737 5600 6100 5900 6100 738 Wire Wire Line 739 6000 5900 6000 6800 740 Wire Wire Line 741 6000 6800 6400 6800 742 Wire Wire Line 743 6100 5700 6100 6200 744 Wire Wire Line 745 6100 6200 6400 6200 746 $Comp 747 L Jumper:Jumper_2_Bridged LK7 748 U 1 1 61EC346B 749 P 6600 8400 750 F 0 "LK7" H 6600 8595 50 0000 C CNN 751 F 1 "Jumper_2_Bridged" H 6600 8504 50 0000 C CNN 752 F 2 "" H 6600 8400 50 0001 C CNN 753 F 3 "~" H 6600 8400 50 0001 C CNN 754 1 6600 8400 755 1 0 0 -1 756 $EndComp 757 Wire Wire Line 758 6400 8000 6200 8000 759 Wire Wire Line 760 6200 8000 6200 8400 761 Wire Wire Line 762 6200 8400 6400 8400 763 Wire Wire Line 764 6200 8000 6200 7400 765 Wire Wire Line 766 6200 7400 6400 7400 767 Connection ~ 6200 8000 768 Wire Wire Line 769 6200 7400 6200 6600 770 Wire Wire Line 771 6200 6600 6400 6600 772 Connection ~ 6200 7400 773 Wire Wire Line 774 6200 6600 6200 6000 775 Wire Wire Line 776 6200 6000 6400 6000 777 Connection ~ 6200 6600 778 Wire Wire Line 779 7000 6100 7100 6100 780 Wire Wire Line 781 7000 6700 7100 6700 782 Wire Wire Line 783 7000 7300 7100 7300 784 Wire Wire Line 785 7000 7900 7100 7900 786 Text GLabel 6900 8400 2 50 Input ~ 0 787 5V 788 Wire Wire Line 789 6900 8400 6800 8400 790 Text GLabel 7200 8300 1 50 Input ~ 0 791 5V 792 Wire Wire Line 793 7200 8300 7200 8400 794 Text GLabel 7200 9500 3 50 Input ~ 0 795 0V 796 Wire Wire Line 797 7200 9500 7200 9400 798 Text GLabel 6100 8400 0 50 Output ~ 0 799 BUFFER_ENABLE 800 Wire Wire Line 801 6100 8400 6200 8400 802 Connection ~ 6200 8400 803 Text Notes 1400 10600 0 50 ~ 0 804 PL4 introduced for the two separate connections\non the original board. 805 Text Label 2100 5400 2 50 ~ 0 806 D[0..7] 807 Text Label 2100 3800 2 50 ~ 0 808 A[0..15] 809 Text Label 2100 3100 2 50 ~ 0 810 KBD[0..3] 811 Text Label 2100 2300 2 50 ~ 0 812 RA[0..7] 813 Text GLabel 2300 2100 0 50 Output ~ 0 814 ~WE 815 Text GLabel 2500 2200 0 50 Output ~ 0 816 ~RAS 817 Text GLabel 2700 2300 0 50 Output ~ 0 818 ~CAS 819 Wire Wire Line 820 2900 2300 2700 2300 821 Text Label 2900 3200 2 50 ~ 0 822 KBD0 823 Text Label 2900 3300 2 50 ~ 0 824 KBD1 825 Text Label 2900 3400 2 50 ~ 0 826 KBD2 827 Text Label 2900 3500 2 50 ~ 0 828 KBD3 829 $Comp 830 L power:PWR_FLAG #FLG0104 831 U 1 1 62281B8F 832 P 2100 10100 833 F 0 "#FLG0104" H 2100 10175 50 0001 C CNN 834 F 1 "PWR_FLAG" H 2100 10274 50 0000 C CNN 835 F 2 "" H 2100 10100 50 0001 C CNN 836 F 3 "~" H 2100 10100 50 0001 C CNN 837 1 2100 10100 838 1 0 0 -1 839 $EndComp 840 Connection ~ 2100 10100 841 Wire Wire Line 842 2100 10100 2600 10100 843 $Comp 844 L power:PWR_FLAG #FLG0105 845 U 1 1 62281BE9 846 P 2100 10200 847 F 0 "#FLG0105" H 2100 10275 50 0001 C CNN 848 F 1 "PWR_FLAG" H 2100 10373 50 0000 C CNN 849 F 2 "" H 2100 10200 50 0001 C CNN 850 F 3 "~" H 2100 10200 50 0001 C CNN 851 1 2100 10200 852 -1 0 0 1 853 $EndComp 854 Connection ~ 2100 10200 855 Wire Wire Line 856 2100 10200 2600 10200 857 Wire Wire Line 858 4000 900 4000 800 859 Wire Wire Line 860 4000 1550 4000 1250 861 $Comp 862 L power:+5V #PWR0101 863 U 1 1 61F9A343 864 P 3500 8600 865 F 0 "#PWR0101" H 3500 8450 50 0001 C CNN 866 F 1 "+5V" H 3515 8773 50 0000 C CNN 867 F 2 "" H 3500 8600 50 0001 C CNN 868 F 3 "" H 3500 8600 50 0001 C CNN 869 1 3500 8600 870 1 0 0 -1 871 $EndComp 872 $Comp 873 L power:GND #PWR0102 874 U 1 1 61FAE014 875 P 3300 9500 876 F 0 "#PWR0102" H 3300 9250 50 0001 C CNN 877 F 1 "GND" H 3305 9327 50 0000 C CNN 878 F 2 "" H 3300 9500 50 0001 C CNN 879 F 3 "" H 3300 9500 50 0001 C CNN 880 1 3300 9500 881 1 0 0 -1 882 $EndComp 883 $Comp 884 L power:-5V #PWR0103 885 U 1 1 61FAE0AD 886 P 3500 9600 887 F 0 "#PWR0103" H 3500 9700 50 0001 C CNN 888 F 1 "-5V" H 3515 9773 50 0000 C CNN 889 F 2 "" H 3500 9600 50 0001 C CNN 890 F 3 "" H 3500 9600 50 0001 C CNN 891 1 3500 9600 892 1 0 0 -1 893 $EndComp 894 Wire Wire Line 895 2700 8800 3500 8800 896 Wire Wire Line 897 2600 9800 3500 9800 898 Wire Wire Line 899 2700 9300 3300 9300 900 Connection ~ 3500 8800 901 Wire Wire Line 902 3500 8800 3700 8800 903 Wire Wire Line 904 3300 9500 3300 9400 905 Connection ~ 3300 9300 906 Wire Wire Line 907 3300 9300 3700 9300 908 Wire Wire Line 909 3500 9800 3500 9700 910 Connection ~ 3500 9800 911 Wire Wire Line 912 3500 9800 3700 9800 913 $Comp 914 L power:PWR_FLAG #FLG0101 915 U 1 1 61FD1C8B 916 P 3500 8700 917 F 0 "#FLG0101" H 3500 8775 50 0001 C CNN 918 F 1 "PWR_FLAG" V 3500 8828 50 0000 L CNN 919 F 2 "" H 3500 8700 50 0001 C CNN 920 F 3 "~" H 3500 8700 50 0001 C CNN 921 1 3500 8700 922 0 -1 -1 0 923 $EndComp 924 $Comp 925 L power:PWR_FLAG #FLG0102 926 U 1 1 61FD1D09 927 P 3500 9700 928 F 0 "#FLG0102" H 3500 9775 50 0001 C CNN 929 F 1 "PWR_FLAG" V 3500 9828 50 0000 L CNN 930 F 2 "" H 3500 9700 50 0001 C CNN 931 F 3 "~" H 3500 9700 50 0001 C CNN 932 1 3500 9700 933 0 1 1 0 934 $EndComp 935 $Comp 936 L power:PWR_FLAG #FLG0103 937 U 1 1 61FD8A1C 938 P 3300 9400 939 F 0 "#FLG0103" H 3300 9475 50 0001 C CNN 940 F 1 "PWR_FLAG" V 3300 9528 50 0000 L CNN 941 F 2 "" H 3300 9400 50 0001 C CNN 942 F 3 "~" H 3300 9400 50 0001 C CNN 943 1 3300 9400 944 0 -1 -1 0 945 $EndComp 946 Connection ~ 3300 9400 947 Wire Wire Line 948 3300 9400 3300 9300 949 Wire Wire Line 950 3500 8600 3500 8700 951 Connection ~ 3500 8700 952 Wire Wire Line 953 3500 8700 3500 8800 954 Connection ~ 3500 9700 955 Wire Wire Line 956 3500 9600 3500 9700 957 $Comp 958 L power:PWR_FLAG #FLG0106 959 U 1 1 62024979 960 P 4000 1250 961 F 0 "#FLG0106" H 4000 1325 50 0001 C CNN 962 F 1 "PWR_FLAG" V 4000 1378 50 0000 L CNN 963 F 2 "" H 4000 1250 50 0001 C CNN 964 F 3 "~" H 4000 1250 50 0001 C CNN 965 1 4000 1250 966 0 1 1 0 967 $EndComp 968 Connection ~ 4000 1250 969 Wire Wire Line 970 4000 1250 4000 1200 971 $Comp 972 L power:PWR_FLAG #FLG0107 973 U 1 1 620249E5 974 P 3800 1350 975 F 0 "#FLG0107" H 3800 1425 50 0001 C CNN 976 F 1 "PWR_FLAG" V 3800 1650 50 0000 L CNN 977 F 2 "" H 3800 1350 50 0001 C CNN 978 F 3 "~" H 3800 1350 50 0001 C CNN 979 1 3800 1350 980 0 1 1 0 981 $EndComp 982 Connection ~ 3800 1350 983 Wire Wire Line 984 3800 1350 3800 1200 985 Text Notes 4550 1400 0 50 ~ 0 986 Note that KiCad gets upset\nwhen connecting passives\nto power input pins. 987 Wire Bus Line 988 2100 1600 2100 1900 989 Wire Bus Line 990 2100 3100 2100 3400 991 Wire Bus Line 992 2100 2300 2100 3000 993 Wire Bus Line 994 2100 5400 2100 6100 995 Wire Bus Line 996 2100 3800 2100 5300 997 $EndSCHEMATC