{"error":{"root_cause":[{"type":"query_shard_exception","reason":"failed to create query: {\n \"regexp\" : {\n \"keyword\" : {\n \"value\" : \".*74LS148扩展中断(基于8051 Proteus仿真).*\",\n \"flags_value\" : 65535,\n \"max_determinized_states\" : 10000,\n \"boost\" : 1.0\n }\n }\n}","index_uuid":"SON-ziQURzKK3JljPlVlCQ","index":"recommend_keyword_search_v1"}],"type":"search_phase_execution_exception","reason":"all shards failed","phase":"query","grouped":true,"failed_shards":[{"shard":0,"index":"recommend_keyword_search_v1","node":"-Gn7X2aRSFmN2hMyaNEUCA","reason":{"type":"query_shard_exception","reason":"failed to create query: {\n \"regexp\" : {\n \"keyword\" : {\n \"value\" : \".*74LS148扩展中断(基于8051 Proteus仿真).*\",\n \"flags_value\" : 65535,\n \"max_determinized_states\" : 10000,\n \"boost\" : 1.0\n }\n }\n}","index_uuid":"SON-ziQURzKK3JljPlVlCQ","index":"recommend_keyword_search_v1","caused_by":{"type":"illegal_argument_exception","reason":"expected ')' at position 33"}}}]},"status":400}
74LS148 , 8 线-3 线优先编码器,proteus中,I0口变化时,GS、EO不变?
2013-01-24 13:16
本帖最后由 xuleicqnc 于 2012-5-5 12:20 编辑 protens仿真74ls148编码器中,给零输入端一个低电平,GS端怎么没有低电平输出?按照真值表的话,只要是有触发GS会置零的。为什么会出现这种情况.高手救助呀!!!!!!!!!!!
2012-05-05 12:14
图片是4片74ls148级联实现的32-5编码,那要实现88路编码用几片74ls148怎么连?相应的用74ls138解码电路怎么连?最好附上连接原理图
2019-03-11 14:29
74ls148一定要拉高嘛?(新手喷轻点)
2022-01-28 14:27
我们在设计8位抢答器过程中想利用三位74LS148译码器的输出来表示驱动器CD4511的三位输入和第四位输入。我们目前推出来的结果是D=A'B'C';但是需要用74LS30八输入与非门和74LS08与门来表示该结果需
2018-07-19 09:30
`谁能用面包板帮我设计一个数字抢答器啊,原件有八个开关,八个电阻,一个数码管,一个74LS48,一个74LS148,一个74LS279,一个74LS00,还有导线若干`
2017-05-24 17:16
电路如图74LS148编码后是000~111,按照这个电路图显示器就会显示0~7,求大神改一下使其显示1~8,抢答后蜂鸣器响2秒后停止,计时器显示该刻时间 qq878992601本人联系方式[qq]878992601[/qq]
2016-09-25 15:47
如题哪位好心人有proteus带74ls151的元件库
2017-12-04 19:07
74LS138译码器是什么?74LS138译码器的扩展方法是什么?
2022-01-19 07:14
LED灯按一次开关就亮一次松开开关灯就灭了,就想按一次开关LED就一直亮着怎么弄 这图哪里错了求指教啊
2015-06-05 20:27