📄 chap.5.parallel_io.ps
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431 Dl2275 2117 MXY14 57 Dl2304 2117 MXY-14 57 Dl2555 1801 MXY-14 -57 Dl2527 1801 MXY14 -57 Dl0 431 Dl2527 2117 MXY14 57 Dl2555 2117 MXY-14 57 Dl2771 1801 MXY-14 -57 Dl2743 1801 MXY14 -57 Dl0 431 Dl2743 2117 MXY14 57 Dl2771 2117 MXY-14 57 Dl2808 1801 MXY-14 -57 Dl2779 1801 MXY14 -57 Dl0 431 Dl2779 2117 MXY14 57 Dl2808 2117 MXY-14 57 Dl3168 1801 MXY-14 -57 Dl3139 1801 MXY14 -57 Dl0 431 Dl3139 2117 MXY14 57 Dl3168 2117 MXY-14 57 Dl1713 2607 MXY0 432 Dl1699 2981 MXY14 57 Dl1728 2981 MXY-14 57 Dl1785 2607 MXY0 432 Dl1771 2981 MXY14 57 Dl1800 2981 MXY-14 57 Dl2110 2607 MXY0 432 Dl2095 2981 MXY14 57 Dl2124 2981 MXY-14 57 Dl3225 3039 MXY0 -432 Dl3240 2665 MXY-14 -57 Dl3211 2665 MXY14 -57 Dl3153 3039 MXY0 -432 Dl3168 2665 MXY-14 -57 Dl3139 2665 MXY14 -57 Dl2829 3039 MXY0 -432 Dl2843 2665 MXY-14 -57 Dl2815 2665 MXY14 -57 Dl12 s1822 1993(Address)N2326 1995(Data)N2829(Control)X22 s1857 2087(.)N1945(.)X2033(.)X1857 1851(.)N1945(.)X2033(.)X2326(.)X2414(.)X2502(.)X2326 2103(.)N2414(.)X2502(.)X2865(.)X2953(.)X3041(.)X2865 1851(.)N2953(.)X3041(.)X14 s2110 1576(CPU)N2355(\(68000\))X2739(Chip)X2721 3183(External)N3129(Inputs)X1606(External)X2014(Outputs)X1720 3298(E.g.,)N1956(+-5V)X1793 3428(Lamps)N2808 3442(Switches)N22 s1857 2810(.)N1945(.)X2033(.)X2865 2823(.)N2953(.)X3041(.)X14 s2779 3318(E.g.,)N3015(+-5V)X1966 2427(Peripheral)N2456(\(8255\))X2784(Chip)X3 f12 s1659 3647(Figure)N1956(5.2.)X2124(Relationship)X2665(of)X2769(Peripheral)X1741 3759(Chip)N1967(\(8255\))X2247(to)X2351(CPU)X2572(\(68000\))X2900(Chip.)X1 f576 3919(In)N689(the)X840(case)X1039(of)X1152(the)X1303(chemical)X1685(process)X2006(example,)X2390(3)X2471(of)X2584(the)X2735(external)X9 f3079(\261)X1 f3165(5)X3246(volt)X3430(outputs)X3747(could)X3995(be)X4120(con-)X576 4031(nected)N864(to)X975(switches)X1342(which)X1613(would)X1889(in)X2000(turn)X2191(control)X2500(the)X2654(states)X2904(of)X3020(valves.)X3350(One)X3546(of)X3662(the)X9 f3816(\261)X1 f3904(5V)X4056(inputs)X576 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4731(an)N698(input)X927(or)X1038(output.)X1363(The)X1544(24)X1671(bits)X1841(are)X1989(accessed)X2356(from)X2573(the)X2721(68000)X2991(CPU)X3207(via)X3355(three)X3578(8-bit)X3790(device)X4072(regis-)X576 4843(ters:)N1056 4983(Mem.)N1307(location)X2256(Register)X2601(name)X1056 5095($FE050000)N2016(Port)X2200(A)X2293(Register)X2638(\(PAreg\))X1056 5207($FE050010)N2016(Port)X2200(B)X2288(Register)X2633(\(PBreg\))X1056 5319($FE050020)N2016(Port)X2200(C)X2288(Register)X2633(\(PBreg\))X49 p%%Page: 49 412 s 0 xH 0 xS 1 f3 f576 400(57:017)N872(CIE)X1 f2329(-)X2385(49)X2505(-)X3 f3717(Lecture)X4062(Notes)X1 f11 s3207 1287 MXY0 -144 Dl-1151 0 Dl0 144 Dl1151 0 Dl2200 855(.)N2200 876(.)N2200 896(.)N2200 917(.)N2200 937(.)N2200 958(.)N2200 978(.)N2200 999(.)N2344 855(.)N2344 876(.)N2344 896(.)N2344 917(.)N2344 937(.)N2344 958(.)N2344 978(.)N2344 999(.)N2487 855(.)N2487 876(.)N2487 896(.)N2487 917(.)N2487 937(.)N2487 958(.)N2487 978(.)N2487 999(.)N2631 855(.)N2631 876(.)N2631 896(.)N2631 917(.)N2631 937(.)N2631 958(.)N2631 978(.)N2631 999(.)N2775 855(.)N2775 876(.)N2775 896(.)N2775 917(.)N2775 937(.)N2775 958(.)N2775 978(.)N2775 999(.)N2919 855(.)N2919 876(.)N2919 896(.)N2919 917(.)N2919 937(.)N2919 958(.)N2919 978(.)N2919 999(.)N3063 855(.)N3063 876(.)N3063 896(.)N3063 917(.)N3063 937(.)N3063 958(.)N3063 978(.)N3063 999(.)N2200 1143(.)N2200 1164(.)N2200 1184(.)N2200 1205(.)N2200 1225(.)N2200 1246(.)N2200 1266(.)N2200 1287(.)N2344 1143(.)N2344 1164(.)N2344 1184(.)N2344 1205(.)N2344 1225(.)N2344 1246(.)N2344 1266(.)N2344 1287(.)N2487 1143(.)N2487 1164(.)N⌨️ 快捷键说明
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