:instd_logic;intr:instd_logic;data_i:instd_logic_v
:instd_logic;intr:instd_logic;data_i:instd_logic_v
;entity ad_controller isport(reset:instd_logic;clk
;entity ad_controller isport(reset:instd_logic;clk
td_logic_arith.all;use ieee.std_logic_unsigned.all
td_logic_arith.all;use ieee.std_logic_unsigned.all
ibrary ieee;use ieee.std_logic_1164.all;use ieee.s
ibrary ieee;use ieee.std_logic_1164.all;use ieee.s
=0,读取数据。构造体的三进程描述：进程1：描述次态逻辑进程2：描述状态寄存器进程3：描述输出逻辑l
=0, du qu shu ju gou zao ti de san jin cheng miao shu jin cheng 1 miao shu ci tai luo ji jin cheng 2 miao shu zhuang tai ji cun qi jin cheng 3 miao shu shu chu luo ji l
s="1",wr=1,rd=1,intr,转换结束，开始读read2: cs="1",wr=1,rd
s="1",wr=1,rd=1,intr, zhuan huan jie shu kai shi du read2: cs="1",wr=1,rd
0804开始转换convert：cs=1,wr=1,rd=1,ad0804进行数据转换read1:c
0804 kai shi zhuan huan convert cs=1,wr=1,rd=1,ad0804 jin hang shu ju zhuan huan read1:c
码表示为0000010000晋中劳动保障网104个状态如下：idle: cs="0",wr=0,rd=1 启动ad
ma biao shi wei 0000010000 jin zhong lao dong bao zhang wang 104 ge zhuang tai ru xia idle: cs="0",wr=0,rd=1 qi dong ad
32v，而低4位0101是0.1v，最后的电压输出结果是0.32v+0.1v=0.42v，它的bcd
32v er di 4 wei 0101 shi 0.1v zui hou de dian ya shu chu jie guo shi 0.32v+0.1v=0.42v ta de bcd
的电压值。本模块的功能仿真结果如图3所示；当转换数据为00010101，通过晋中劳动保障网查表高4位0001是0.
de dian ya zhi ben mo kuai de gong neng fang zhen jie guo ru tu 3 suo shi dang zhuan huan shu ju wei 00010101 tong guo jin zhong lao dong bao zhang wang cha biao gao 4 wei 0001 shi 0.
.02v；考虑到直接使用乘法计算对应的电压值将耗用大量的fpga内部组件，本设计用查表命令来得到正确
.02v kao lv dao zhi jie shi yong cheng fa ji suan dui ying de dian ya zhi jiang hao yong da liang de fpga nei bu zu jian ben she ji yong cha biao ming ling lai de dao zheng que
辨率为0.02v。常用测量方法是：当读取到db7～db0转换值是xxh时，电压测量值为u≈xxh×0
bian lv wei 0.02v chang yong ce liang fang fa shi dang du qu dao db7 db0 zhuan huan zhi shi xxh shi dian ya ce liang zhi wei u xxh 0
果输入信号vin为0～5v电压范围，则每两个状态值为晋中劳动保障网5/(256-1)，约为0.0196v，故测量分
guo shu ru xin hao vin wei 0 5v dian ya fan wei ze mei liang ge zhuang tai zhi wei jin zhong lao dong bao zhang wang 5/(256-1) yue wei 0.0196v gu ce liang fen
码管显示。adc0804功能介绍：adc0804是8位模数转换器，它的输出状态共有28=256种，如
ma guan xian shi adc0804 gong neng jie shao adc0804 shi 8 wei mo shu zhuan huan qi ta de shu chu zhuang tai gong you 28=256 zhong ru
理得到模拟电压的数字码，再输入数码管获得被测电压的数字显示。 此电压表的测量范晋中劳动保障网围：0～5v，三位数
li de dao mo ni dian ya de shu zi ma zai shu ru shu ma guan huo de bei ce dian ya de shu zi xian shi ci dian ya biao de ce liang fan jin zhong lao dong bao zhang wang wei 0 5v san wei shu
作时，系统按一定的速率采集输入的模拟电压，经adc0804转换为8位数字量，此8位数字量经fpga处
zuo shi xi tong an yi ding de su lv cai ji shu ru de mo ni dian ya jing adc0804 zhuan huan wei 8 wei shu zi liang ci 8 wei shu zi liang jing fpga chu
扫描、显示模块，产生数码管的片选信号，并将数值处理晋中劳动保障网模块输出的bcd码译成相应的7段数码驱动值。 工
sao miao xian shi mo kuai chan sheng shu ma guan de pian xuan xin hao bing jiang shu zhi chu li jin zhong lao dong bao zhang wang mo kuai shu chu de bcd ma yi cheng xiang ying de 7 duan shu ma qu dong zhi gong
收a/d转换器传递过来的数字转换值；(2)数据处理模块，将接收到的转换值调整成对应的数字信号；(3)
shou a/d zhuan huan qi chuan di guo lai de shu zi zhuan huan zhi (2) shu ju chu li mo kuai jiang jie shou dao de zhuan huan zhi diao zheng cheng dui ying de shu zi xin hao (3)
08-3芯片，用vhdl语言对它进行设计晋中劳动保障网，实现三大功能模块：(1)控制模块，激活a/d转换器动作、接
08-3 xin pian yong vhdl yu yan dui ta jin hang she ji jin zhong lao dong bao zhang wang shi xian san da gong neng mo kuai (1) kong zhi mo kuai ji huo a/d zhuan huan qi dong zuo jie
数字电压表的硬件结构系统的核心电路由fpga完成，本设计选用了altera公司的eplkl00qc2
shu zi dian ya biao de ying jian jie gou xi tong de he xin dian lu you fpga wan cheng ben she ji xuan yong le altera gong si de eplkl00qc2