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// page no 375
// example no 12.3
// CHECK PENDING INTERRUPT
clc;
printf('RIM instruction interpretation \n \n');
printf('D7=SID Serial input data if any \n');
printf('D6,D5,D4= I7.5,I6.5,I5.5 Pending interrupts: 1= pending \n');
printf('D3=IE Interrupt enable flag: 1= enabled \n');
printf('D2,D1,D0= M7.5,M6.5,M5.5 Interrupt masks: 1= masked \n \n \n');
printf('Instructions \n \n');
printf(' RIM \n'); // Read interrupt mask
printf(' MOV B,A \n'); // save mask information
printf(' ANI 20H \n'); // check whether RST 6.5 is pending
printf(' JNZ NEXT \n');
printf(' EI \n');
printf(' RET \n'); // RST 6.5 is not pending, return to main program
printf('NEXT: MOV A,B \n'); // get bit pattern; RST 6.5 is pending
printf(' ANI 0DH \n'); // enables RST 6.5 by setting D1=0
printf(' ORI 08H\n'); // enable SIM by setting D3=1
printf(' SIM \n');
printf(' JMP SERV \n'); // jump to service routine for RST 6.5
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