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五.综合题(15分)有一个微型计算机系统(见下列图),外部模拟信号从AD0809的IN3引脚输入,要求答复以下问题
(1)AD0809和片外RAM6264的地址范围是多少?
(2)编程实现,将图中A/D转换器的数据采样进来,放入外部RAM6264中(从起始存储单元开始顺序存放),并且根据当A/D数据的大于0C0H时,点亮红灯(LED1)当数据小于40H时,点亮绿灯(LED2)o说明图中,网络标号相同(如ALE、ADCS等)的线连在一起;网络标号VCC就是电压+5V;假设P
1.6引脚输出高电平,红灯(LED1)亮,反之那么暗;假设P
1.7引脚输出高电平,绿灯(LED2)亮,反之那么暗;74LS373是锁存器,其作用是将数据/地址总线ADO〜7的数据地址信号别离;U3(27C512)为片外ROM;U4
(6264)为片外RAM;74LS138为3-8译码器;AD0809的EOC信号为1表示AD转换结束此时读AD0809输出的数据是有效数据;
⑤START信号为1启动AD0809的转换;RAMCS和ADCS信号均为低电平有效;ALEINIIN2模拟信号输入年~JN41JN5IN6INSVCCALEU6nADDAADDBADDCoeEOCSTARTINTIINTOil[£4-T-10uF/50V110KC1514To1119□cryRESET-C8189~3fXU274HC373U327C512P10/TpurrP12P13P14P15P16P17T1TORXDTXDXIX2RESETEA/VPPOOP01P02P03P04P05P06P07P20P21P22P23P24P25P26P27ALE/PPSENWRRD39ADOA8A911A1O—AllA1ZA132~klT28AIS2AO10PSEN2220A0AlA2A3A4A5A6A7A8A9A10AllA12A13A14A15OECE11ADOIF液商汤FTads1FaD619AD724A1OAllA12PAMCSVCC21272026ADOADIADZAD3AD41ADSAD6AD728+5V30ALE29PSENR310KU574HC138A131VCC61514131211ADCSRAMCS#includeabsacc.h#includereg5l.h#defineucharunsignedchar#defineIN3XBYTE[0x2000]#defineU4XBYTE[0x8000]uchari;ucharidata*x;ucharxdata*adadr;ucharxdata*waicun;sbitP10=PlA0;sbitPll=PlAl;sbitP12=P1A2;sbitP13=P1A3;sbitP16=P1A6;sbitP17=P1A7;sbitadbusy=P3A3;voidmainP10=0;Pll=l;P12=0;P13=l;adadr=IN3;waicun=U4;adadr=0;••1=1;••1=1;whileadbusy=0;x=*adadr;*waicun=x;P0=*waicun;ifP00xc0P16=l;Pl7=0;elseifP00x40P16=0;P17=l;ADIADZAD3AD4ADSAD6AD733ADI437ADZ736AD3835AD41334ADS1433AD61732AD718DIQiD3Q3D5Q5D7Q7D6Q6D4Q4D2Q2DOQ0LEOE5Al96AZ89A3712A4615AS516A6419A73A825A924A1021All23A122A1326A1427AIS19128137146564173A0DOAlDIA2D2A3D3A4D4A5D5A6D6A7D7A8A9A10AllA12WEOEVBCSlCS2A142Al53AY0BY1CY2Y3Y4E3Y5ElY6E2Y7。