通信系统大型实验板上有2组拨码开关，分别为S1、S2，相对应的管脚为114、116、117、118、119、120、121、122、130、131、132、133、135、136、137、138，拨S1或S2的ON或OFF，观测被控制的输出端口（定义为pal1和pal2）变化，对应ON输出端口为高电平，对应OFF输出端口为低电平，此为简单的FPGA测试程序dial_test.v-Large-scale experiment on-board communication system DIP switch 2 groups, respectively, S1, S2, corresponding to the pin for the 114,116,117,118,119,120,121,122,130,131,132,133,135 , 136,137,138, allocated S1 or S2 to ON or OFF, observing the controlled output (defined as pal1 and pal2) changes, the corresponding output port ON is high, corresponding to OFF output is low, this FPGA for the simple test program dial_test.v