DAP-16M2

* O100-01-H101 (DPM2UP) DRAWING NO. 41286623-001-02 PAGE 31

1070 * 1071 * OPSR: OP CODE TABLE SEARCH ROUTINE 1072 * 1073 * 1074 * CALLING SEQUENCE: 1075 * JST OPSR 1076 * ......RETURN IF MACHINE OP 1077 * 1078 * IF THE OP-CODE IS A PSEUDO-OP, CONTROL 1079 * WILL BE PASSED TO THE PROPER PROCESSING 1080 * ROUTINE. THIS ROUTINE CHECKS FOR INHIBITED 1081 * ASSEMBLY AND UNDEFINED AND ILLEGAL OPCODES. 1082 * 1083 * 1084 01470 0 000000 OPSR DAC ** 1085 01471 0 35 00777 LDX XF5D POINTER TO FREE ENTRY IN TABLE 1086 01472 0 02 00450 LDA SYL FIRST 2 CHARACTERS OF TARGET NAME 1087 01473 0 05 00620 ERA B3 INDIRECT ALLOWED BIT 1088 01474 1 04 00000 STA 0,1 PLACE WORD IN TABLE 1089 01475 0 02 00451 LDA SYL+1 LAST 2 CHARACTERS IN TARGET NAME 1090 01476 0 05 00620 ERA B3 MEMORY REFERENCE BIT 1091 01477 1 04 00001 STA 1,1 PLACE WORD IN TABLE 1092 01500 0 35 00774 LDX TOPS ADDRESS OF FIRST WORD IN TABLE 1093 01501 1 02 00000 OPS1 LDA 0,1 FETCH FIRST WORD OF ENTRY FROM TABLE 1094 01502 0 04 00472 STA CBT1 SAVE IT FOR LATER USE 1095 01503 0 05 00450 ERA SYL MERGE WITH FIRST TWO CHARACTERS 1096 * OF TARGET NAME 1097 01504 0 03 00665 ANA CHR2 ELIMINATE CODE BITS 1098 01505 100040 SZE SKIP IF CHARACTERS MATCH 1099 01506 0 01 01536 JMP OPS2 OTHERWISE ADVANCE TO NEXT ENTRY 1100 01507 1 02 00001 LDA 1,1 FETCH SECOND WORD OF ENTRY FROM TABLE 1101 01510 0 04 00474 STA CBT2 SAVE IT FOR LATER USE 1102 01511 0 05 00451 ERA SYL+1 MERGE WITH SECOND TWO CHARACTERS OF 1103 * TARGET NAME 1104 01512 0 03 00665 ANA CHR2 ELIMINATE CODE BITS 1105 01513 100040 SZE SKIP IF CHARACTERS MATCH 1106 01514 0 01 01536 JMP OPS2 OTHERWISE ADVANCE TO NEXT ENTRY 1107 01515 1 02 00002 LDA 2,1 FETCH THIRD WORD OF ENTRY - CONTAINS 1108 * OPCODE IF A MACHINE-OP, OR ADDRESS OF 1109 * PROCESSOR IF PSEUDO-OP. 1110 01516 0 04 00437 STA WORD SAVE IT 1111 01517 0 02 00472 LDA CBT1 RETRIEVE FIRST WORD OF ENTRY 1112 01520 100400 SPL IF POSITIVE: ITS A MACHINE OP 1113 01521 0 01 01540 JMP OPS3 OTHERWISE IT'S A PSEUDO-OP 1114 01522 0414 77 DACX LGL 1 A(1)= ADDRESS REQUIRED FLAG 1115 01523 100400 SPL SKIP IF ADDRESS NOT REQUIRED 1116 01524 0 12 00424 IRS ADRF SET ADDRESS REQUIRED FLAG 1117 01525 0414 77 LGL 1 A(1)= INDIRECT ALLOWED FLAG 1118 01526 100400 SPL SKIP IF INDIRECT NOT ALLOWED 1119 01527 0 12 00425 IRS INDA SET INDIRECT ALLOWED FLAG