FTTalk
Enter the DCS number between 500 and 603 for the DCS code you want to use.
So for example D023N you would enter 500 if you want to send the reverse code so for example D026R then you add 200 to the DCS number so 502+200=702. I think only the 991A can actually send DCS codes as well as being able to generate CTCSS tones. So it is an option in the FTTALK configuration file.
Also the Yeasu list does not exactly agree with the standard DCS list there are a couple of differences so you may have to try codes on either side of the one asked for as I don't know whether the yaesu list has just a couple of printing errors or is the real table used by the radio.
The first number is the Yaesu number the second is the DCS Number/Code.

500 023 
501 025 
502 026 
503 031 
504 032 
505 036 
506 043 
507 047 
508 051 
509 053 
510 054 
511 065 
512 071 
513 072 
514 073 
515 074 
516 114 
517 115 
518 116 
519 122 
520 125 
521 131 
522 132 
523 134 
524 143 
525 145 
526 152 
527 155 
528 156 
529 162 
530 165 
531 172 
532 174 
533 205 
534 212 
535 223 
536 225
537 226
538 243
539 244
540 245
541 246
542 251
543 252
544 255
545 261
546 263
547 265
548 266
549 271
550 274
551 306
552 311
553 315
554 325
555 331
556 332
557 343
558 346
559 351
560 356
561 364
562 365
563 371
564 411
565 412
566 413
567 423
568 431
569 432
570 445
571 446
572 452
573 454
574 455
575 462
576 464
577 465
578 466
579 503
580 506
581 516
582 523
583 526
584 532
585 546
586 565
587 606
588 612
589 624
590 627
591 631
592 632
593 654
594 662
595 664
596 703
597 712
598 723
599 731
600 732
601 734
602 743
603 754