This is the experiment I did before. Experiments 1 and 2 are planned to be done one per day. Here is the third experiment. The counter experiment makes the LED light flip every 50ms. The principle is
if(ReceiveBuf==0x55)
{ SBUF = SendBuf[0]; //If the received value is 0x55, send out 0xaa in SendBuf[0]
while(!TI); //wait to send
TI=0; //If the transmission is completed, clear TI to 0
P2=0x00;
BEEP=
Yesterday I worked on the infrared communication device topic of the 2013 electronics competition. I spent the whole morning and afternoon adjusting it, but I still can't achieve modulation using LM56