protues中74ls148连74ls279锁存器后148的gs端始终是高电平protues中74ls148连74ls279锁存器后148的gs端始终是高电平protues中74ls148连74ls279锁存器后148的gs端始终是高电平protues中74ls148连74ls279锁存器后148的gs端始终是高电平protues中74ls148连74ls279锁存器后148的gs端始终是高电平