1 EESchema Schematic File Version 4 2 LIBS:AcornElectronMainboard-cache 3 EELAYER 26 0 4 EELAYER END 5 $Descr A4 11693 8268 6 encoding utf-8 7 Sheet 3 9 8 Title "" 9 Date "" 10 Rev "" 11 Comp "" 12 Comment1 "" 13 Comment2 "" 14 Comment3 "" 15 Comment4 "" 16 $EndDescr 17 $Comp 18 L DRAM:4164 IC4 19 U 1 1 61D7F23A 20 P 2350 2650 21 F 0 "IC4" H 2350 3225 50 0000 C CNN 22 F 1 "4164" H 2350 3134 50 0000 C CNN 23 F 2 "" H 2300 2650 50 0001 C CNN 24 F 3 "" H 2300 2650 50 0001 C CNN 25 1 2350 2650 26 1 0 0 -1 27 $EndComp 28 $Comp 29 L DRAM:4164 IC5 30 U 1 1 61D7F241 31 P 3750 2650 32 F 0 "IC5" H 3750 3225 50 0000 C CNN 33 F 1 "4164" H 3750 3134 50 0000 C CNN 34 F 2 "" H 3700 2650 50 0001 C CNN 35 F 3 "" H 3700 2650 50 0001 C CNN 36 1 3750 2650 37 1 0 0 -1 38 $EndComp 39 $Comp 40 L DRAM:4164 IC6 41 U 1 1 61D7F248 42 P 5150 2650 43 F 0 "IC6" H 5150 3225 50 0000 C CNN 44 F 1 "4164" H 5150 3134 50 0000 C CNN 45 F 2 "" H 5100 2650 50 0001 C CNN 46 F 3 "" H 5100 2650 50 0001 C CNN 47 1 5150 2650 48 1 0 0 -1 49 $EndComp 50 $Comp 51 L DRAM:4164 IC7 52 U 1 1 61D7F24F 53 P 6550 2650 54 F 0 "IC7" H 6550 3225 50 0000 C CNN 55 F 1 "4164" H 6550 3134 50 0000 C CNN 56 F 2 "" H 6500 2650 50 0001 C CNN 57 F 3 "" H 6500 2650 50 0001 C CNN 58 1 6550 2650 59 1 0 0 -1 60 $EndComp 61 Entry Wire Line 62 1800 2800 1900 2700 63 Entry Wire Line 64 1800 2900 1900 2800 65 Entry Wire Line 66 1800 3000 1900 2900 67 Connection ~ 3000 3300 68 Wire Bus Line 69 3000 3300 1800 3300 70 Entry Wire Line 71 2900 2600 3000 2700 72 Entry Wire Line 73 2900 2700 3000 2800 74 Entry Wire Line 75 2900 2800 3000 2900 76 Entry Wire Line 77 2900 2900 3000 3000 78 Entry Wire Line 79 2900 3000 3000 3100 80 Connection ~ 3200 3300 81 Wire Bus Line 82 3200 3300 3000 3300 83 Entry Wire Line 84 3200 2800 3300 2700 85 Entry Wire Line 86 3200 2900 3300 2800 87 Entry Wire Line 88 3200 3000 3300 2900 89 Entry Wire Line 90 4300 2600 4400 2700 91 Entry Wire Line 92 4300 2700 4400 2800 93 Entry Wire Line 94 4300 2800 4400 2900 95 Entry 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~ 0 420 0V 421 Wire Wire Line 422 1600 1200 1600 1400 423 Wire Wire Line 424 1600 1400 2800 1400 425 Wire Wire Line 426 7000 1400 7000 2300 427 Wire Wire Line 428 7000 2300 6900 2300 429 Wire Wire Line 430 5500 2300 5600 2300 431 Wire Wire Line 432 5600 2300 5600 1400 433 Connection ~ 5600 1400 434 Wire Wire Line 435 5600 1400 7000 1400 436 Wire Wire Line 437 4100 2300 4200 2300 438 Wire Wire Line 439 4200 2300 4200 1400 440 Connection ~ 4200 1400 441 Wire Wire Line 442 4200 1400 5600 1400 443 Wire Wire Line 444 2700 2300 2800 2300 445 Wire Wire Line 446 2800 2300 2800 1400 447 Connection ~ 2800 1400 448 Wire Wire Line 449 2800 1400 4200 1400 450 Wire Bus Line 451 7200 3300 7700 3300 452 Text GLabel 7700 1600 2 50 BiDi ~ 0 453 RAM[0..3] 454 Text GLabel 7700 3300 2 50 Input ~ 0 455 RA[0..7] 456 Text Label 7600 3300 2 50 ~ 0 457 A[0..7] 458 Text GLabel 7700 3700 2 50 Input ~ 0 459 ~WE 460 Text GLabel 7700 3500 2 50 Input ~ 0 461 ~RAS 462 Wire Wire Line 463 1700 2500 2000 2500 464 Text 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Connection ~ 3150 3500 510 Wire Wire Line 511 7100 2400 7100 1900 512 Wire Wire Line 513 7100 1900 7700 1900 514 Wire Wire Line 515 5700 2400 5700 1900 516 Wire Wire Line 517 5700 1900 7100 1900 518 Connection ~ 7100 1900 519 Wire Wire Line 520 4300 2400 4300 1900 521 Wire Wire Line 522 4300 1900 5700 1900 523 Connection ~ 5700 1900 524 Wire Wire Line 525 2900 2400 2900 1900 526 Wire Wire Line 527 2900 1900 4300 1900 528 Connection ~ 4300 1900 529 Wire Wire Line 530 1900 3100 3300 3100 531 Wire Wire Line 532 3300 3100 4700 3100 533 Wire Wire Line 534 4700 3100 6100 3100 535 Wire Bus Line 536 1800 2800 1800 3300 537 Wire Bus Line 538 3200 2800 3200 3300 539 Wire Bus Line 540 4600 2800 4600 3300 541 Wire Bus Line 542 6000 2800 6000 3300 543 Wire Bus Line 544 5800 2700 5800 3300 545 Wire Bus Line 546 7200 2700 7200 3300 547 Wire Bus Line 548 4400 2700 4400 3300 549 Wire Bus Line 550 3000 2700 3000 3300 551 Wire Bus Line 552 1600 1600 7700 1600 553 $EndSCHEMATC