Author Topic: Tektronix 4924 Tape Drive Emulator (Read 34780 times)

WaveyDipole · « **Reply #175 on:** July 14, 2021, 08:21:44 am »

Fair enough and it is clearly evident that this is still not working right. The console output shows that we are getting to the end of the file and apparently not breaking out after the first INPUT command. However, I am struggling to see what else we are missing. I had a look over the manual again this morning hoping that a fresh pair of eyes might help.

Section 4 of the 070-2270-00_4051_GPIB_HW_Supp_Jul81.pdf manual describes in detail the processing of the INPUT command which in summary is as follows:

Initially the 4051 sets attention and the device responds by goint to attention and accepting the command from the Tek. The primary and then secondar address is sent using normal handshaking.

The device waits until ATN goes up and starts sending data. The manual again describes the normal handshaking process.

Apparently the Tek accepts data until "a CR delimiter is received, an alternate delimiter is received, or until 72 characters are received, whichever occurs first.". At this point the Tek stops the data transfer by holding NRFD low and processes the information. This takes between 4ms and 12ms. The Tek "searches the contents of the I/O buffer for valid numeric data which it then converts to floating point format and assigns to a variable in RAM. If a string is specified, it will read all the characters up to the delimiter into the string variable.

The Tek then resumes collecting more data up to a delimiter or 72 characters from the device and again stops and processes the buffer.

After all variables have been assigned, the Tek "terminates the operation by activating ATN and issuing an UNTALK/UNLISTEN sequence over GPIB".

So what I understood from this is that the ATN comes at the end of each INPUT command once all the provided variables have been read to stop transmission.

Of all the ASCII data files looked at so far, none have lines linger than 72 characters, so the Tek should read each line up to the CR, and then pause (for up to 12ms) and process that line. If all variables in the INPUT statement have been satisfied it should then issue ATN and stop transmission. If not, then it should proceed to read up to the next delimiter or until 72 characters have been reached and again process that line until such time that all variables have been read. It then issues ATN to stop transmission. If there is any more data to be read then the process is repeated in the next INPUT statement.

As you pointed out, the interpretation of the terminators is left up to the Tek so the emulator sends byte-by-byte and waits for the Tek to stop transmission once the INPUT statement has been satisfied.

I have pushed up an update. It doesn't really change anything much except that the close function is commented out and it adds a a couple of debug information bits. I would like to see the console output when we are reading one variable at a time. I will let you know if I have any bright ideas in the meantime.

BTW, I have also been doing a bit of work on the binary format in READ, i.e. reading the binary header then reading x bytes according to the length specified in the header. Are there any files on the SD card that I can test with this? I have it working in principle in both actual binary and HEX format but would like to test it on real data files. Did you do any testing of the binary read?

mmcgraw74 · « **Reply #176 on:** July 14, 2021, 12:06:40 pm »

I will check out your v30 version and get back to you.

Yes, files 3 and 6 in the UTILITIES directory are both BINARY data files captured from tape.
However, my capture program is over serial, so my BASIC program to recover an entire tape converts each byte of a binary file into two ASCII HEX characters to ensure that the serial program does not interpret and strip control characters from the transfer.

My continuedDEV.ino READ_file and READ_one both have logic for BINARY files (PROGRAM or DATA) to convert each two ASCII HEX characters into a single binary byte. I have been using Realterm successfully as the PC serial program at 115200 8n1 to display the ASCII and BINARY files over debug serial output.

I will try to capture a single numeric and single string variable GPIB transfer on my 4052 with my logic analyzer.

I have found this website HEX to binary converter useful in decoding one of my ASCII HEX files to binary to examine with HxD: https://tomeko.net/online_tools/hex_to_file.php?lang=en

mmcgraw74 · « **Reply #177 on:** July 14, 2021, 02:33:32 pm »

mmcgraw74 · « **Reply #178 on:** July 14, 2021, 07:05:23 pm »

mmcgraw74 · « **Reply #179 on:** July 14, 2021, 07:16:19 pm »

that was only the first half of the trace listing.

Here is the second half of the trace listing:

[code]
500 8 ns CE 1 0 1 1 1 0
501 8 ns CE 1 0 1 1 0 0
502 21.38 us CE 1 0 0 1 0 0
503 32.94 us CE 1 1 0 1 0 0
504 89.16 us CE 1 1 0 1 1 0
505 3.312 us FF 1 1 0 1 1 0
506 29.66 us FF 1 0 0 1 1 0
507 59.69 us FF 1 0 1 1 1 0
508 32.77 us CD 1 0 1 1 1 0
509 8 ns C9 1 0 1 1 1 0
510 8 ns DF 1 0 1 1 1 0
511 8 ns C9 1 0 1 1 1 0
512 9.176 us C9 1 0 1 1 0 0
513 8 ns C9 1 0 1 1 1 0
514 8 ns C9 1 0 1 1 0 0
515 25.74 us C9 1 0 0 1 0 0
516 33.46 us C9 1 1 0 1 0 0
517 84.29 us C9 1 1 0 1 1 0
518 3.320 us FF 1 1 0 1 1 0
519 303.7 us FF 1 0 0 1 1 0
520 59.68 us FF 1 0 1 1 1 0
521 82.38 us F1 1 0 1 1 1 0
522 8 ns F1 1 0 1 1 1 0
523 8 ns DD 1 0 1 1 1 0
524 8 ns D1 1 0 1 1 1 0
525 9.176 us D1 1 0 1 1 0 0
526 8 ns D1 1 0 1 1 1 0
527 8 ns D1 1 0 1 1 0 0
528 33.22 us D1 1 0 0 1 0 0
529 32.93 us D1 1 1 0 1 0 0
530 77.34 us D1 1 1 0 1 1 0
531 3.320 us FF 1 1 0 1 1 0
532 14.26 us FF 1 0 0 1 1 0
533 59.68 us FF 1 0 1 1 1 0
534 48.17 us DF 1 0 1 1 1 0
535 8 ns C9 1 0 1 1 1 0
536 8 ns DF 1 0 1 1 1 0
537 8 ns C9 1 0 1 1 1 0
538 9.176 us C9 1 0 1 1 0 0
539 8 ns C9 1 0 1 1 1 0
540 8 ns C9 1 0 1 1 0 0
541 38.09 us C9 1 0 0 1 0 0
542 32.94 us C9 1 1 0 1 0 0
543 72.46 us C9 1 1 0 1 1 0
544 3.320 us FF 1 1 0 1 1 0
545 18.08 us FF 1 0 0 1 1 0
546 59.68 us FF 1 0 1 1 1 0
547 44.36 us CA 1 0 1 1 1 0
548 8 ns FF 1 0 1 1 1 0
549 8 ns CE 1 0 1 1 1 0
550 8 ns CA 1 0 1 1 1 0
551 9.168 us CA 1 0 1 1 0 0
552 8 ns CA 1 0 1 1 0 0
553 8 ns CA 1 0 1 1 1 0
554 8 ns CA 1 0 1 1 0 0
555 42.43 us CA 1 0 0 1 0 0
556 32.94 us CA 1 1 0 1 0 0
557 68.12 us CA 1 1 0 1 1 0
558 3.312 us FB 1 1 0 1 1 0
559 8 ns FF 1 1 0 1 1 0
560 22.42 us FF 1 0 0 1 1 0
561 59.69 us FF 1 0 1 1 1 0
562 40.01 us DF 1 0 1 1 1 0
563 8 ns FF 1 0 1 1 1 0
564 8 ns DF 1 0 1 1 1 0
565 9.184 us DF 1 0 1 1 0 0
566 8 ns DF 1 0 1 1 1 0
567 8 ns DF 1 0 1 1 0 0
568 19.55 us DF 1 0 0 1 0 0
569 32.42 us DF 1 1 0 1 0 0
570 97.78 us DF 1 1 0 1 1 0
571 3.320 us FF 1 1 0 1 1 0
572 21.04 us FF 1 0 0 1 1 0
573 59.68 us FF 1 0 1 1 1 0
574 41.39 us DF 1 0 1 1 1 0
575 8 ns DF 1 0 1 1 1 0
576 8 ns FF 1 0 1 1 1 0
577 8 ns DF 1 0 1 1 1 0
578 9.176 us DF 1 0 1 1 0 0
579 8 ns DF 1 0 1 1 1 0
580 8 ns DF 1 0 1 1 0 0
581 17.65 us DF 1 0 0 1 0 0
582 32.94 us DF 1 1 0 1 0 0
583 92.91 us DF 1 1 0 1 1 0
584 3.312 us FF 1 1 0 1 1 0
585 26.98 us FF 1 0 0 1 1 0
586 59.68 us FF 1 0 1 1 1 0
587 35.46 us CE 1 0 1 1 1 0
588 8 ns EE 1 0 1 1 1 0
589 8 ns CE 1 0 1 1 1 0
590 9.184 us CE 1 0 1 1 0 0
591 8 ns CE 1 0 1 1 1 0
592 8 ns CE 1 0 1 1 0 0
593 23.58 us CE 1 0 0 1 0 0
594 32.94 us CE 1 1 0 1 0 0
595 86.98 us CE 1 1 0 1 1 0
596 3.312 us FF 1 1 0 1 1 0
597 31.85 us FF 1 0 0 1 1 0
598 60.22 us FF 1 0 1 1 1 0
599 30.06 us CF 1 0 1 1 1 0
600 8 ns CE 1 0 1 1 1 0
601 8 ns DF 1 0 1 1 1 0
602 8 ns CE 1 0 1 1 1 0
603 9.176 us CE 1 0 1 1 0 0
604 8 ns CE 1 0 1 1 1 0
605 8 ns CE 1 0 1 1 0 0
606 28.98 us CE 1 0 0 1 0 0
607 32.94 us CE 1 1 0 1 0 0
608 81.57 us CE 1 1 0 1 1 0
609 3.320 us FF 1 1 0 1 1 0
610 37.25 us FF 1 0 0 1 1 0
611 59.68 us FF 1 0 1 1 1 0
612 31.38 us CB 1 0 1 1 1 0
613 8 ns FB 1 0 1 1 1 0
614 8 ns CF 1 0 1 1 1 0
615 8 ns CB 1 0 1 1 1 0
616 9.176 us CB 1 0 1 1 0 0
617 8 ns CB 1 0 1 1 1 0
618 8 ns CB 1 0 1 1 0 0
619 27.13 us CB 1 0 0 1 0 0
620 33.46 us CB 1 1 0 1 0 0
621 82.90 us CB 1 1 0 1 1 0
622 3.312 us FB 1 1 0 1 1 0
623 8 ns FF 1 1 0 1 1 0
624 35.92 us FF 1 0 0 1 1 0
625 59.69 us FF 1 0 1 1 1 0
626 26.50 us FD 1 0 1 1 1 0
627 8 ns F1 1 0 1 1 1 0
628 8 ns DF 1 0 1 1 1 0
629 8 ns D1 1 0 1 1 1 0
630 9.176 us D1 1 0 1 1 0 0
631 8 ns D1 1 0 1 1 1 0
632 8 ns D1 1 0 1 1 0 0
633 33.06 us D1 1 0 0 1 0 0
634 32.41 us D1 1 1 0 1 0 0
635 78.02 us D1 1 1 0 1 1 0
636 3.320 us FF 1 1 0 1 1 0
637 13.05 us FF 1 0 0 1 1 0
638 60.21 us FF 1 0 1 1 1 0
639 48.86 us DF 1 0 1 1 1 0
640 8 ns FF 1 0 1 1 1 0
641 8 ns DF 1 0 1 1 1 0
642 9.176 us DF 1 0 1 1 0 0
643 8 ns DF 1 0 1 1 0 0
644 8 ns DF 1 0 1 1 1 0
645 8 ns DF 1 0 1 1 0 0
646 38.46 us DF 1 0 0 1 0 0
647 32.94 us DF 1 1 0 1 0 0
648 72.09 us DF 1 1 0 1 1 0
649 3.312 us FF 1 1 0 1 1 0
650 19.51 us FF 1 0 0 1 1 0
651 59.68 us FF 1 0 1 1 1 0
652 42.93 us DF 1 0 1 1 1 0
653 8 ns FF 1 0 1 1 1 0
654 8 ns DF 1 0 1 1 1 0
655 9.184 us DF 1 0 1 1 0 0
656 8 ns DF 1 0 1 1 1 0
657 8 ns DF 1 0 1 1 0 0
658 43.34 us DF 1 0 0 1 0 0
659 32.93 us DF 1 1 0 1 0 0
660 73.48 us DF 1 1 0 1 1 0
661 3.320 us FF 1 1 0 1 1 0
662 17.06 us FF 1 0 0 1 1 0
663 59.68 us FF 1 0 1 1 1 0
664 45.37 us DF 1 0 1 1 1 0
665 8 ns DF 1 0 1 1 1 0
666 8 ns FF 1 0 1 1 1 0
667 8 ns DF 1 0 1 1 1 0
668 9.176 us DF 1 0 1 1 0 0
669 8 ns DF 1 0 1 1 1 0
670 8 ns DF 1 0 1 1 0 0
671 41.42 us DF 1 0 0 1 0 0
672 32.94 us DF 1 1 0 1 0 0
673 69.14 us DF 1 1 0 1 1 0
674 3.312 us FF 1 1 0 1 1 0
675 21.42 us FF 1 0 0 1 1 0
676 59.68 us FF 1 0 1 1 1 0
677 41.02 us DF 1 0 1 1 1 0
678 8 ns FF 1 0 1 1 1 0
679 8 ns DF 1 0 1 1 1 0
680 9.184 us DF 1 0 1 1 0 0
681 8 ns DF 1 0 1 1 1 0
682 8 ns DF 1 0 1 1 0 0
683 18.54 us DF 1 0 0 1 0 0
684 32.41 us DF 1 1 0 1 0 0
685 92.54 us DF 1 1 0 1 1 0
686 3.312 us FF 1 1 0 1 1 0
687 26.29 us FF 1 0 0 1 1 0
688 59.68 us FF 1 0 1 1 1 0
689 36.15 us CE 1 0 1 1 1 0
690 8 ns CE 1 0 1 1 1 0
691 8 ns DF 1 0 1 1 1 0
692 8 ns CE 1 0 1 1 1 0
693 9.176 us CE 1 0 1 1 0 0
694 8 ns CE 1 0 1 1 1 0
695 8 ns CE 1 0 1 1 0 0
696 22.89 us CE 1 0 0 1 0 0
697 32.94 us CE 1 1 0 1 0 0
698 87.66 us CE 1 1 0 1 1 0
699 3.320 us FF 1 1 0 1 1 0
700 32.22 us FF 1 0 0 1 1 0
701 59.68 us FF 1 0 1 1 1 0
702 30.22 us C8 1 0 1 1 1 0
703 8 ns FF 1 0 1 1 1 0
704 8 ns C8 1 0 1 1 1 0
705 9.176 us C8 1 0 1 1 0 0
706 8 ns C8 1 0 1 1 1 0
707 8 ns C8 1 0 1 1 1 0
708 8 ns C8 1 0 1 1 0 0
709 28.82 us C8 1 0 0 1 0 0
710 32.94 us C8 1 1 0 1 0 0
711 87.99 us C8 1 1 0 1 1 0
712 3.312 us FF 1 1 0 1 1 0
713 96 ns FF 1 1 0 1 1 0
714 8 ns FF 1 1 0 1 1 0
715 30.74 us FF 1 0 0 1 1 0
716 60.21 us FF 1 0 1 1 1 0
717 31.07 us F1 1 0 1 1 1 0
718 8 ns F1 1 0 1 1 1 0
719 8 ns D5 1 0 1 1 1 0
720 8 ns D1 1 0 1 1 1 0
721 9.176 us D1 1 0 1 1 0 0
722 8 ns D1 1 0 1 1 1 0
723 8 ns D1 1 0 1 1 0 0
724 27.97 us D1 1 0 0 1 0 0
725 32.94 us D1 1 1 0 1 0 0
726 82.58 us D1 1 1 0 1 1 0
727 3.312 us F1 1 1 0 1 1 0
728 8 ns FF 1 1 0 1 1 0
729 36.23 us FF 1 0 0 1 1 0
730 59.68 us FF 1 0 1 1 1 0
731 26.20 us CF 1 0 1 1 1 0
732 8 ns C7 1 0 1 1 1 0
733 8 ns DF 1 0 1 1 1 0
734 8 ns C7 1 0 1 1 1 0
735 9.176 us C7 1 0 1 1 0 0
736 8 ns C7 1 0 1 1 1 0
737 8 ns C7 1 0 1 1 0 0
738 32.31 us C7 1 0 0 1 0 0
739 33.46 us C7 1 1 0 1 0 0
740 77.71 us C7 1 1 0 1 1 0
741 3.320 us FF 1 1 0 1 1 0
742 13.36 us FF 1 0 0 1 1 0
743 59.15 us FF 1 0 1 1 1 0
744 49.61 us CF 1 0 1 1 1 0
745 8 ns FF 1 0 1 1 1 0
746 8 ns CF 1 0 1 1 1 0
747 9.176 us CF 1 0 1 1 0 0
748 8 ns CF 1 0 1 1 0 0
749 8 ns CF 1 0 1 1 1 0
750 8 ns CF 1 0 1 1 0 0
751 38.24 us CF 1 0 0 1 0 0
752 32.41 us CF 1 1 0 1 0 0
753 72.84 us CF 1 1 0 1 1 0
754 3.312 us FF 1 1 0 1 1 0
755 18.23 us FF 1 0 0 1 1 0
756 60.22 us FF 1 0 1 1 1 0
757 49.93 us DF 1 0 1 1 1 0
758 8 ns FF 1 0 1 1 1 0
759 8 ns DF 1 0 1 1 1 0
760 9.184 us DF 1 0 1 1 0 0
761 8 ns DF 1 0 1 1 1 0
762 8 ns DF 1 0 1 1 0 0
763 37.38 us DF 1 0 0 1 0 0
764 32.94 us DF 1 1 0 1 0 0
765 73.16 us DF 1 1 0 1 1 0
766 3.320 us FF 1 1 0 1 1 0
767 18.43 us FF 1 0 0 1 1 0
768 59.69 us FF 1 0 1 1 1 0
769 43.99 us DF 1 0 1 1 1 0
770 9.200 us DF 1 0 1 1 0 0
771 8 ns DF 1 0 1 1 1 0
772 8 ns DF 1 0 1 1 0 0
773 42.26 us DF 1 0 0 1 0 0
774 32.93 us DF 1 1 0 1 0 0
775 68.30 us DF 1 1 0 1 1 0
776 3.312 us FF 1 1 0 1 1 0
777 22.26 us FF 1 0 0 1 1 0
778 59.68 us FF 1 0 1 1 1 0
779 40.18 us CE 1 0 1 1 1 0
780 8 ns FF 1 0 1 1 1 0
781 8 ns CE 1 0 1 1 1 0
782 9.184 us CE 1 0 1 1 0 0
783 8 ns CE 1 0 1 1 1 0
784 8 ns CE 1 0 1 1 0 0
785 18.85 us CE 1 0 0 1 0 0
786 32.94 us CE 1 1 0 1 0 0
787 91.70 us CE 1 1 0 1 1 0
788 3.312 us FF 1 1 0 1 1 0
789 27.66 us FF 1 0 0 1 1 0
790 60.22 us FF 1 0 1 1 1 0
791 34.25 us CE 1 0 1 1 1 0
792 8 ns CE 1 0 1 1 1 0
793 8 ns DE 1 0 1 1 1 0
794 8 ns CE 1 0 1 1 1 0
795 9.176 us CE 1 0 1 1 0 0
796 8 ns CE 1 0 1 1 1 0
797 8 ns CE 1 0 1 1 0 0
798 24.78 us CE 1 0 0 1 0 0
799 32.42 us CE 1 1 0 1 0 0
800 92.54 us CE 1 1 0 1 1 0
801 3.320 us FF 1 1 0 1 1 0
802 25.74 us FF 1 0 0 1 1 0
803 59.15 us FF 1 0 1 1 1 0
804 37.22 us DF 1 0 1 1 1 0
805 8 ns C7 1 0 1 1 1 0
806 8 ns FF 1 0 1 1 1 0
807 8 ns C7 1 0 1 1 1 0
808 9.176 us C7 1 0 1 1 0 0
809 8 ns C7 1 0 1 1 1 0
810 8 ns C7 1 0 1 1 1 0
811 8 ns C7 1 0 1 1 0 0
812 21.81 us C7 1 0 0 1 0 0
813 32.94 us C7 1 1 0 1 0 0
814 88.74 us C7 1 1 0 1 1 0
815 3.312 us FF 1 1 0 1 1 0
816 298.2 us FF 1 0 0 1 1 0
817 59.68 us FF 1 0 1 1 1 0
818 81.64 us F1 1 0 1 1 1 0
819 8 ns FF 1 0 1 1 1 0
820 8 ns D1 1 0 1 1 1 0
821 9.176 us D1 1 0 1 1 0 0
822 8 ns D1 1 0 1 1 1 0
823 8 ns D1 1 0 1 1 0 0
824 33.44 us D1 1 0 0 1 0 0
825 32.94 us D1 1 1 0 1 0 0
826 77.11 us D1 1 1 0 1 1 0
827 3.320 us FF 1 1 0 1 1 0
828 14.49 us FF 1 0 0 1 1 0
829 59.68 us FF 1 0 1 1 1 0
830 47.95 us DF 1 0 1 1 1 0
831 8 ns FF 1 0 1 1 1 0
832 8 ns DF 1 0 1 1 1 0
833 15.44 us DF 1 0 1 1 0 0
834 8 ns DF 1 0 1 1 1 0
835 8 ns DF 1 0 1 1 0 0
836 33.64 us DF 1 0 0 1 0 0
837 33.46 us DF 1 1 0 1 0 0
838 76.38 us DF 1 1 0 1 1 0
839 3.312 us FF 1 1 0 1 1 0
840 14.70 us FF 1 0 0 1 1 0
841 59.15 us FF 1 0 1 1 1 0
842 48.27 us DF 1 0 1 1 1 0
843 9.200 us DF 1 0 1 1 0 0
844 8 ns DF 1 0 1 1 1 0
845 8 ns DF 1 0 1 1 0 0
846 39.58 us DF 1 0 0 1 0 0
847 32.94 us DF 1 1 0 1 0 0
848 70.98 us DF 1 1 0 1 1 0
849 3.320 us FF 1 1 0 1 1 0
850 19.56 us FF 1 0 0 1 1 0
851 60.22 us FF 1 0 1 1 1 0
852 42.34 us DF 1 0 1 1 1 0
853 8 ns FF 1 0 1 1 1 0
854 8 ns DF 1 0 1 1 1 0
855 9.176 us DF 1 0 1 1 0 0
856 8 ns DF 1 0 1 1 0 0
857 8 ns DF 1 0 1 1 1 0
858 8 ns DF 1 0 1 1 0 0
859 16.16 us DF 1 0 0 1 0 0
860 32.93 us DF 1 1 0 1 0 0
861 94.40 us DF 1 1 0 1 1 0
862 3.312 us FF 1 1 0 1 1 0
863 24.97 us FF 1 0 0 1 1 0
864 59.68 us FF 1 0 1 1 1 0
865 36.85 us BF 1 0 1 1 1 0
866 8 ns FF 1 0 1 1 1 0
867 8 ns BF 1 0 1 1 1 0
868 608 ns BA 1 0 1 1 1 0
869 8 ns BA 1 0 1 1 1 0
870 8 ns BE 1 0 1 1 1 0
871 8 ns BA 1 0 1 1 1 0
872 9.176 us BA 1 0 1 1 0 0
873 8 ns BA 1 0 1 1 1 0
874 8 ns BA 1 0 1 1 0 0
875 21.03 us BA 1 0 0 1 0 0
876 32.94 us BA 1 1 0 1 0 0
877 89.51 us BA 1 1 0 1 1 0
878 2.688 us FA 1 1 0 1 1 0
879 632 ns FF 1 1 0 1 1 0
880 29.30 us FF 1 0 0 1 1 0
881 59.68 us FF 1 0 1 1 1 0
882 39.38 us DF 1 0 1 1 1 0
883 8 ns CE 1 0 1 1 1 0
884 8 ns FF 1 0 1 1 1 0
885 8 ns CE 1 0 1 1 1 0
886 9.176 us CE 1 0 1 1 0 0
887 8 ns CE 1 0 1 1 1 0
888 8 ns CE 1 0 1 1 0 0
889 19.13 us CE 1 0 0 1 0 0
890 33.47 us CE 1 1 0 1 0 0
891 90.90 us CE 1 1 0 1 1 0
892 3.312 us FF 1 1 0 1 1 0
893 27.93 us FF 1 0 0 1 1 0
894 59.68 us FF 1 0 1 1 1 0
895 34.51 us C6 1 0 1 1 1 0
896 8 ns F7 1 0 1 1 1 0
897 8 ns C6 1 0 1 1 1 0
898 9.184 us C6 1 0 1 1 0 0
899 8 ns C6 1 0 1 1 1 0
900 8 ns C6 1 0 1 1 0 0
901 25.06 us C6 1 0 0 1 0 0
902 32.41 us C6 1 1 0 1 0 0
903 86.02 us C6 1 1 0 1 1 0
904 3.312 us F7 1 1 0 1 1 0
905 8 ns FF 1 1 0 1 1 0
906 32.79 us FF 1 0 0 1 1 0
907 59.68 us FF 1 0 1 1 1 0
908 29.64 us F9 1 0 1 1 1 0
909 8 ns F1 1 0 1 1 1 0
910 8 ns DF 1 0 1 1 1 0
911 8 ns D1 1 0 1 1 1 0
912 9.176 us D1 1 0 1 1 0 0
913 8 ns D1 1 0 1 1 1 0
914 8 ns D1 1 0 1 1 0 0
915 29.40 us D1 1 0 0 1 0 0
916 32.41 us D1 1 1 0 1 0 0
917 81.68 us D1 1 1 0 1 1 0
918 3.320 us FF 1 1 0 1 1 0
919 37.67 us FF 1 0 0 1 1 0
920 59.68 us FF 1 0 1 1 1 0
921 24.77 us CB 1 0 1 1 1 0
922 8 ns FF 1 0 1 1 1 0
923 8 ns CB 1 0 1 1 1 0
924 9.176 us CB 1 0 1 1 0 0
925 8 ns CB 1 0 1 1 1 0
926 8 ns CB 1 0 1 1 1 0
927 8 ns CB 1 0 1 1 0 0
928 34.27 us CB 1 0 0 1 0 0
929 32.94 us CB 1 1 0 1 0 0
930 82.54 us CB 1 1 0 1 1 0
931 3.312 us FF 1 1 0 1 1 0
932 37.35 us FF 1 0 0 1 1 0
933 59.68 us FF 1 0 1 1 1 0
934 25.09 us CF 1 0 1 1 1 0
935 9.200 us CF 1 0 1 1 0 0
936 8 ns CF 1 0 1 1 1 0
937 8 ns CF 1 0 1 1 0 0
938 33.94 us CF 1 0 0 1 0 0
939 32.42 us CF 1 1 0 1 0 0
940 77.13 us CF 1 1 0 1 1 0
941 3.312 us EF 1 1 0 1 1 0
942 8 ns FF 1 1 0 1 1 0
943 13.94 us FF 1 0 0 1 1 0
944 59.68 us FF 1 0 1 1 1 0
945 48.50 us F2 1 0 1 1 1 0
946 8 ns FF 1 0 1 1 1 0
947 8 ns F2 1 0 1 1 1 0
948 9.176 us F2 1 0 1 1 0 0
949 8 ns F2 1 0 1 1 1 0
950 8 ns F2 1 0 1 1 0 0
951 38.82 us F2 1 0 0 1 0 0
952 33.47 us F2 1 1 0 1 0 0
953 71.19 us F2 1 1 0 1 1 0
954 3.320 us FF 1 1 0 1 1 0
955 19.87 us FF 1 0 0 1 1 0
956 2.992 ms FF 0 0 0 1 1 0
957 27.75 us FF 0 1 1 1 1 0
958 8 ns FF 1 0 0 1 1 0
959 8 ns FF 0 0 0 1 1 0
960 8 ns F3 0 0 0 1 1 0
961 8 ns FF 0 0 0 1 1 0
962 8 ns 93 0 0 0 1 1 0
963 8 ns 92 0 0 0 1 1 0
964 112 ns 92 0 1 1 1 1 0
965 40 ns 93 0 1 1 1 1 0
966 8 ns 93 0 1 1 1 1 0
967 8 ns 92 0 1 1 1 1 0
968 64 ns 92 0 0 1 1 1 0
969 40 ns 92 0 1 1 1 1 0
970 71.73 us 92 0 1 1 1 0 0
971 8 ns 92 0 1 1 1 1 0
972 8 ns 92 0 1 1 1 0 0
973 48.43 us DF 0 0 0 1 0 0
974 26.90 us DF 1 0 0 1 0 0
975 1.165 ms DF 1 0 1 1 0 0
976 8 ns DF 1 0 1 1 0 0
977 8 ns DF 1 0 1 1 0 0
978 8 ns DF 1 1 1 1 0 0
979 77.57 us DF 1 1 1 1 1 0
980 3.320 us FF 1 1 1 1 1 0
981 3.300 s FF 1 1 1 1 1 0
982 32.33 ms FF 1 0 0 1 1 0
983 599.6 us FF 1 0 1 1 1 0
984 8 ns FF 1 0 1 1 1 0
985 8 ns FF 1 0 1 1 1 0
986 8 ns FF 1 1 1 1 1 0
987 108.7 us BF 1 1 1 1 1 0
988 8 ns FF 1 1 1 1 1 0
989 8 ns BF 1 1 1 1 1 0
990 608 ns AD 1 1 1 1 1 0
991 8 ns BD 1 1 1 1 1 0
992 8 ns AD 1 1 1 1 1 0
993 9.184 us AD 1 1 1 1 0 0
994 8 ns AD 1 1 1 1 1 0
995 8 ns AD 1 1 1 1 0 0
996 1.011 s AD 1 1 1 1 0 0
997 33.33 ms AD 1 0 0 1 0 0
998 598.6 us AD 1 0 1 1 0 0
999 8 ns AD 1 0 1 1 0 0
1000 8 ns AD 1 1 1 1 0 0
1001 104.3 us AD 1 1 1 1 1 0
1002 2.688 us ED 1 1 1 1 1 0
1003 624 ns FF 1 1 1 1 1 0
1004 617.4 ms FF 1 1 1 1 1 0
1005 32.41 ms FF 1 0 0 1 1 0
1006 597.5 us FF 1 0 1 1 1 0
1007 8 ns FF 1 0 1 1 1 0
1008 8 ns FF 1 0 1 1 1 0
1009 8 ns FF 1 1 1 1 1 0
1010 55.33 us F2 1 1 1 1 1 0
1011 8 ns FF 1 1 1 1 1 0
1012 8 ns D2 1 1 1 1 1 0
1013 9.176 us D2 1 1 1 1 0 0
1014 8 ns D2 1 1 1 1 1 0
1015 8 ns D2 1 1 1 1 0 0
1016 631.6 ms D2 1 1 1 1 0 0
1017 33.93 ms D2 1 0 0 1 0 0
1018 599.1 us D2 1 0 1 1 0 0
1019 8 ns D2 1 0 1 1

mmcgraw74 · « **Reply #180 on:** July 14, 2021, 07:19:11 pm »

good grief - it still didn't get all the trace.

Here is the end of the trace (hopefully)

Code: [Select]

   1019         8 ns   D2   1    0    1   1   0   0
   1020         8 ns   D2   1    0    1   1   0   0
   1021         8 ns   D2   1    0    1   1   0   0
   1022         8 ns   D2   1    1    1   1   0   0
   1023     36.31 us   D2   1    1    1   1   1   0
   1024     3.312 us   FF   1    1    1   1   1   0
   1025     662.5 ms   FF   1    1    1   1   1   0
   1026     31.47 ms   FF   1    0    0   1   1   0
   1027     599.6 us   FF   1    0    1   1   1   0
   1028         8 ns   FF   1    0    1   1   1   0
   1029         8 ns   FF   1    0    1   1   1   0
   1030         8 ns   FF   1    1    1   1   1   0
   1031     67.88 us   CE   1    1    1   1   1   0
   1032         8 ns   CE   1    1    1   1   1   0
   1033         8 ns   DE   1    1    1   1   1   0
   1034         8 ns   CE   1    1    1   1   1   0
   1035     9.176 us   CE   1    1    1   1   0   0
   1036         8 ns   CE   1    1    1   1   1   0
   1037         8 ns   CE   1    1    1   1   0   0
   1038     912.2 ms   CE   1    1    1   1   0   0
   1039     35.54 ms   CE   1    0    0   1   0   0
   1040     869.8 us   CE   1    0    1   1   0   0
   1041         8 ns   CE   1    0    1   1   0   0
   1042         8 ns   CE   1    1    1   1   0   0
   1043     50.68 us   CE   1    1    1   1   1   0
   1044     3.312 us   FF   1    1    1   1   1   0
   1045     23.98  s   FF   1    1    1   1   1   0
   1046     19.00 ms   FF   0    1    1   1   1   0
   1047     27.76 us   DF   1    1    1   1   1   1
   1048         8 ns   FF   0    1    1   1   1   0
   1049         8 ns   FF   0    1    1   1   1   0
   1050         8 ns   F7   0    1    1   1   1   0
   1051         8 ns   FB   0    1    1   1   1   0
   1052         8 ns   92   0    1    1   1   1   0
   1053     124.7 us   FF   0    0    0   1   1   0
   1054     34.31 us   FF   1    0    0   1   1   0
   1055     156.9 us   FF   0    0    0   1   1   0
   1056     28.28 us   FF   0    1    1   1   1   0
   1057         8 ns   FF   1    0    0   1   1   0
   1058         8 ns   FF   0    0    0   1   1   0
   1059         8 ns   F3   0    0    0   1   1   0
   1060         8 ns   F7   0    0    0   1   1   0
   1061         8 ns   92   0    0    0   1   1   0
   1062       120 ns   92   0    0    1   1   1   0
   1063         8 ns   92   0    1    1   1   1   0
   1064       136 ns   92   0    0    1   1   1   0
   1065         8 ns   92   0    0    1   1   1   0
   1066         8 ns   92   0    1    1   1   1   0
   1067     60.49 us   82   0    1    1   1   1   0
   1068     9.200 us   82   0    1    1   1   0   0
   1069         8 ns   82   0    1    1   1   1   0
   1070         8 ns   82   0    1    1   1   0   0
   1071     49.94 us   CF   0    0    0   1   0   0
   1072     27.43 us   CF   1    0    0   1   0   0
   1073     123.3 ms   CF   1    0    1   1   0   0
   1074         8 ns   CF   1    0    1   1   0   0
   1075         8 ns   CF   1    0    1   1   0   0
   1076         8 ns   CF   1    1    1   1   0   0
   1077     63.82 us   CF   1    1    1   1   1   0
   1078     3.320 us   FF   1    1    1   1   1   0

Time Printed: 14 Jul 2021 09:29:31

Hopefully here is the complete trace zip file:

INP5_6V.zip (6.46 kB - downloaded 29 times.)

WaveyDipole · « **Reply #181 on:** July 14, 2021, 08:15:10 pm »

Thank you for the detailed posts!

From the first post I see that the graphic shows the first 74 bytes read up to E19.40[CR] then a slight pause then an ATN and the byte 01101101 or hex 6D which is the MSA for INPUT. That is in line with the expected behaviour of the Tek but not quite as described. I was expecting a UNT first and then a new cycle of MTA, MSA, data, UNT. The Realterm screenshot shows that the next 74 characters are being read up to -5 when the process evidently hangs. I am not seeing an 'ATN asserted!' after the E19.40[CR] though.

On the graphic, the ATN comes after the handshake on the CR character is complete and the emulator starts handshaking the next character. There is a slightly elongated NDAC bump at this point and then both NDAC and NRFD stay low which means that the Tek is not ready to receive and we have a short pause. The Tek is likely processing the first 74 characters that have been received. Then comes ATN and 6D, however the emulator has already started the next handshake at this point and is not actively listening to the ATN. It is still sitting waiting for NRFD to go high. ATN and NRFD do eventually go high and the Tek has places the 6D on the bus and waits for an acknowledgement of the ATN and MSA command which does not come. Meanwhile the emulator being in send mode continues its attempt to send more data (i.e. the emulator send loop continues) until the process hangs.

I think the emulator needs to check for ATN being asserted during the handshake, probably at the point where the emulator is waiting for NRFD to go high to indicate that the receiver is ready. If it gets an ATN at this point, it needs to immediately drop out of the handshake and go into listening mode.

The other problem is that the MSA apears to be being sent on ATN without preceding UNT to finish the last transmission and or MTA + MSA to start the new INPUT command. There is an issue with that at present, in that the emulator does not remember whether it is in talk or listen mode between successive assertions of the ATN signal. It relies on MTA/MLA being sent followed by MSA to determine that.

I will need to have a think about how to deal with this.

I will also review your further post with the logic analyzer output tomorrow morning.

mmcgraw74 · « **Reply #182 on:** July 14, 2021, 08:39:52 pm »

Sounds like progress!

I will make another attempt to get my 4924 tape drive working again. It should give a definitive trace, but I'll have to create a tape with the same data file.

mmcgraw74 · « **Reply #183 on:** July 14, 2021, 10:28:32 pm »

The 4924 5V power supply NPN transistor is bad. I've ordered a NOS cross reference, but won't get it for a week or so

WaveyDipole · « **Reply #184 on:** July 15, 2021, 11:15:31 am »

Quote from: mmcgraw74 on July 14, 2021, 10:28:32 pm

The 4924 5V power supply NPN transistor is bad. I've ordered a NOS cross reference, but won't get it for a week or so

I hope you don't have a leaky electrolytic capacitor or something causing an excessive current draw. At least the transistor is a relatively simple fix.

I have had a go at implementing possible fixes for the two things I mentioned in my previous post and have uploaded the updated code. Since I don't own a Tek computer, I am unfortunately limited in how far I can test this.

mmcgraw74 · « **Reply #185 on:** July 15, 2021, 01:24:02 pm »

I just tried your v31 on my 4054A and 4052.

the OLD function is not working, but INPUT, CD, FIND are working.
INPUT does take a long time for first command (Send Error reported in debug log), then works for subsequent INPUT.

So I did a FIND@5:2 which opened /root/2

Then:

Code: [Select]

INPUT@5:A$      It took some a couple of seconds to return to BASIC prompt(maybe a timeout?)
A$                     Returned /root/
INPUT@5:A$      Returned to prompt quicker
A$                     Returned /Games/
INPUT@5:A$      Returned to prompt quicker
A$                     Returned /UTILITIES/
PRI@5,19:"ADVENTURE"
FIND@5:51        file 51 is ADVENTURE program
OLD@5:             Hung Tektronix

Serial debug output for this experiment:

So this is progress for INPUT.

Apparently CD works, but OLD Hangs Tektronix power cycle of Tek and Emulator required

4052 2nd test of CD and OLD:

Power up Tek, connect Emulator

FIND@5:1
OLD@5:

Tek hung had to be power cycled.

Here is the serial debug output for this experiment:

WaveyDipole · « **Reply #186 on:** July 15, 2021, 02:18:39 pm »

Ok, so some progress on the INPUT issue at last

The 'Send error' can be ignored. It indicates that either ATN was detected or both NDAC and NRFD were high indicating a fault condition. Either should cause the send loop to abort which is what we are now seeing. The writeByte() function was not originally written to anticipate the controller interrupting the send process as this situation never came up before. I could change change it to send a specific error code for each condition so as to be able to differentiate them. For now I will change the debug message to say something like 'ATN or ERR on send'.

Not sure why the delay before the first INPUT command, but I have also noticed a couple of seconds a delay here with my setup before any any file data is output. The GPIB command comes through on the emulator console almost immediately. It might be a delay reading the SD Card or it may be something else such as timeouts. I have GPIB timeout set at 5 secs but the length of delay in this case is about 2.5 seconds which seems to be comparable to what you have reported. I will look into it.

Regarding OLD, any chance of a snapshot of the trace? I need to see the transition between the two commands (FIND and OLD) if possible. FIND is a listen command, whereas old is a TALK command. I am interested in whether the Tek is sending a UNL at then end of FIND, or at least an MTA before the MSA for OLD. Thanks.

mmcgraw74 · « **Reply #187 on:** July 15, 2021, 03:02:55 pm »

WaveyDipole · « **Reply #188 on:** July 15, 2021, 05:18:23 pm »

Thank you although a decoding of the hex characters doesn't seem to make much sense. There are UNT and UNL characters evident but also a 7F (127). There seem to be NULL and other random characters being sent while ATN is asserted which doesn't make sense. Anything send during ATN should be a a primary or secondary address, or a GPIB command character.

The randomness of the characters is such that I would begin to wonder whether there is a problem with the mechanical connection or something nearby inducing EMF into the wires...

HPIB STATE - State Listing

Code: [Select]

Label    >   Time     STAT    DATA ATN NDAC NFRD EOI DAV SRQ
Base     > Relative   Binary  Hex  Bin Bina Bina Bin Bin Bin
__________ _________ ________ ____ ___ ____ ____ ___ ___ ___

      0     37.52 us 10010100   25 0    0    1   1   0   0	MLA
      1     65.79 us 10000100   25 0    0    0   1   0   0
      2     11.45 us 10001100   25 0    1    0   1   0   0
      3     18.10 us 10101100   25 0    1    0   1   1   0
      4     31.74 us 10101100   7D 0    1    0   1   1   0	SECRET?
      5         8 ns 11101101   7F 1    1    0   1   1   0	?
      6         8 ns 10101100   7F 0    1    0   1   1   0	?
      7       336 ns 10101100   7B 0    1    0   1   1   0	FIND
      8     83.62 us 10100100   7B 0    0    0   1   1   0
      9         8 ns 10101100   7B 0    1    0   1   1   0
     10         8 ns 10100100   7B 0    0    0   1   1   0
     11     25.38 us 10110100   7B 0    0    1   1   1   0
     12     42.34 us 10010100   7B 0    0    1   1   0   0
     13     96.24 us 10000100   7B 0    0    0   1   0   0
     14     11.44 us 10001100   7B 0    1    0   1   0   0
     15     15.93 us 10101100   7B 0    1    0   1   1   0
     16     19.30 us 10101101   7B 1    1    0   1   1   0	DATA
     17     37.15 us 10101101   78 1    1    0   1   1   0
     18         8 ns 10101101   60 1    1    0   1   1   0	`
     19        24 ns 10101101   20 1    1    0   1   1   0	SPC
     20     61.41 us 10100101   20 1    0    0   1   1   0	
     21         8 ns 10101101   20 1    1    0   1   1   0
     22         8 ns 10100101   20 1    0    0   1   1   0
     23     1.311 ms 10110101   20 1    0    1   1   1   0
     24     15.68 us 10010101   20 1    0    1   1   0   0
     25     129.4 us 10000101   20 1    0    0   1   0   0
     26     11.45 us 10001101   20 1    1    0   1   0   0
     27     38.81 us 10101101   20 1    1    0   1   1   0
     28     41.80 us 10101101   31 1    1    0   1   1   0	1
     29     64.15 us 10100101   31 1    0    0   1   1   0
     30         8 ns 10101101   31 1    1    0   1   1   0
     31         8 ns 10100101   31 1    0    0   1   1   0
     32     37.77 us 10110101   31 1    0    1   1   1   0
     33     20.42 us 10010101   31 1    0    1   1   0   0
     34     124.7 us 10000101   31 1    0    0   1   0   0
     35     11.44 us 10001101   31 1    1    0   1   0   0
     36     15.79 us 10101101   31 1    1    0   1   1   0
     37     32.86 us 00101101   31 1    1    0   0   1   0
     38     27.70 us 00101101   3D 1    1    0   0   1   0	=
     39       160 ns 00101101   1D 1    1    0   0   1   0	(group separator)
     40         8 ns 00101101   1D 1    1    0   0   1   0
     41         8 ns 00101101   0D 1    1    0   0   1   0	CR
     42     68.24 us 00100101   0D 1    0    0   0   1   0
     43         8 ns 00101101   0D 1    1    0   0   1   0
     44         8 ns 00100101   0D 1    0    0   0   1   0
     45     37.76 us 00110101   0D 1    0    1   0   1   0
     46     43.93 us 00010101   0D 1    0    1   0   0   0
     47     101.2 us 00000101   0D 1    0    0   0   0   0
     48     11.45 us 00001101   0D 1    1    0   0   0   0
     49     39.82 us 00101101   0D 1    1    0   0   1   0
     50     21.98 us 10101101   0D 1    1    0   1   1   0
     51     56.33 us 10101100   0D 0    1    0   1   1   0	?
     52     32.90 us 10100100   0D 0    0    0   1   1   0
     53         8 ns 10101100   0D 0    1    0   1   1   0
     54         8 ns 10100100   0D 0    0    0   1   1   0
     55     53.48 us 10100100   5F 0    0    0   1   1   0	UNT
     56     27.04 ms 10110100   5F 0    0    1   1   1   0
     57        24 ns 10111100   5F 0    1    1   1   1   0
     58     42.91 us 10011100   5F 0    1    1   1   0   0
     59     17.82 us 10000100   5F 0    0    0   1   0   0
     60         8 ns 10001100   5F 0    1    0   1   0   0
     61         8 ns 10000100   5F 0    0    0   1   0   0
     62     23.31 us 10010100   5F 0    0    1   1   0   0
     63     35.98 us 10000100   5F 0    0    0   1   0   0
     64     11.45 us 10001100   5F 0    1    0   1   0   0
     65     34.52 us 10101100   5F 0    1    0   1   1   0
     66     27.51 us 10101100   7F 0    1    0   1   1   0
     67       232 ns 10101100   3F 0    1    0   1   1   0	UNL
     68     87.06 us 10100100   3F 0    0    0   1   1   0
     69         8 ns 10101100   3F 0    1    0   1   1   0
     70         8 ns 10100100   3F 0    0    0   1   1   0
     71     26.14 us 10110100   3F 0    0    1   1   1   0
     72     38.26 us 10010100   3F 0    0    1   1   0   0
     73     115.8 us 10000100   3F 0    0    0   1   0   0
     74     11.45 us 10001100   3F 0    1    0   1   0   0
     75     23.56 us 10101100   3F 0    1    0   1   1   0
     76     35.50 us 10100100   3F 0    0    0   1   1   0
     77       112 ns 10100100   39 0    0    0   1   1   0	?
     78         8 ns 10100100   38 0    0    0   1   1   0	?
     79         8 ns 10100100   00 0    0    0   1   1   0	?
     80     27.30 us 10100101   00 1    0    0   1   1   0	DATA
     81     837.4 us 10110101   00 1    0    1   1   1   0
     82         8 ns 10110101   00 1    0    1   1   1   0
     83         8 ns 11111101   00 1    1    1   1   1   0
     84     4.477  s 10111101   00 1    1    1   1   1   0
     85     18.28 ms 10111100   00 0    1    1   1   1   0	?
     86     25.98 us 10110100   00 0    0    1   1   1   0
     87         8 ns 10100100   00 0    0    0   1   1   0
     88         8 ns 10101100   00 0    1    0   1   1   0
     89         8 ns 10100100   00 0    0    0   1   1   0
     90     2.808 us 11100100   3F 0    0    0   1   1   0	UNL
     91         8 ns 11111101   3F 1    1    1   1   1   0
     92         8 ns 10100100   3F 0    0    0   1   1   0
     93        64 ns 10100100   7F 0    0    0   1   1   0	?
     94         8 ns 10100100   3F 0    0    0   1   1   0	UNL
     95     20.42 us 10110100   3F 0    0    1   1   1   0
     96     36.64 us 10110100   39 0    0    1   1   1   0	?
     97         8 ns 10110100   38 0    0    1   1   1   0	?
     98         8 ns 10110100   30 0    0    1   1   1   0	?
     99         8 ns 10110100   20 0    0    1   1   1   0	?
    100     38.46 us 10010100   20 0    0    1   1   0   0
    101     63.45 us 10000100   20 0    0    0   1   0   0
    102     11.45 us 10001100   20 0    1    0   1   0   0
    103     19.38 us 10101100   20 0    1    0   1   1   0
    104     23.01 us 10101101   20 1    1    0   1   1   0	DATA
    105     27.54 us 00101101   20 1    1    0   0   1   0
    106     28.23 us 00101101   66 1    1    0   0   1   0	f
    107       192 ns 00101101   46 1    1    0   0   1   0	F
    108     35.46 us 00100101   46 1    0    0   0   1   0
    109         8 ns 00101101   46 1    1    0   0   1   0
    110         8 ns 00100101   46 1    0    0   0   1   0
    111     23.94 us 00110101   46 1    0    1   0   1   0
    112        24 ns 00111101   46 1    1    1   0   1   0
    113     34.98 us 00011101   46 1    1    1   0   0   0
    114     38.77 us 00111101   46 1    1    1   0   1   0
    115     21.96 us 10111101   46 1    1    1   1   1   0
    116     69.57 us 10111100   46 0    1    1   1   1   0	?	(F)
    117     35.77 us 10100100   46 0    0    0   1   1   0
    118         8 ns 10111100   46 0    1    1   1   1   0
    119         8 ns 10100100   46 0    0    0   1   1   0
    120     23.31 us 10110100   46 0    0    1   1   1   0
    121     26.36 us 10110100   44 0    0    1   1   1   0	?	(D)
    122         8 ns 10110100   40 0    0    1   1   1   0	?	(@)
    123     37.91 us 10010100   40 0    0    1   1   0   0
    124     74.29 us 10000100   40 0    0    0   1   0   0
    125     11.45 us 10001100   40 0    1    0   1   0   0
    126     38.40 us 10101100   40 0    1    0   1   1   0
    127     37.62 us 10100100   40 0    0    0   1   1   0
    128       168 ns 10100100   00 0    0    0   1   1   0	?
    129     32.02 us 10100101   00 1    0    0   1   1   0	DATA
    130     49.58 us 10110101   00 1    0    1   1   1   0

Time Printed: 15 Jul 2021 08:53:45

Its a bit odd that there seems to be no hex 64 (MSA for OLD) being sent?

Noted regarding hex 7F (127) being EOT. I have also seen the DC3 (device control 3) byte in a listing somewhere (manual?) and wondered what its purpose is.

mmcgraw74 · « **Reply #189 on:** July 15, 2021, 05:35:04 pm »

According to the 4924 tape service manual, 127 is the EOF character in a file.

I have seen NULL and DC3 characters in ASCII data files, particularly in tape file headers I have extracted from recovered tapes.

BTW - I have been making sure to put a CR with nothing else after the last line in ASCII PROGRAMs. This may cause the Tektronix to stop fetching more lines of characters and end the OLD command.

But the current OLD not working issue - no lines are transferred.

I'll check the 4924 description of the SAVE command - it could be the 4924 or Tektronix adds an EOF character after the Tektronix ends the SAVE command

mmcgraw74 · « **Reply #190 on:** July 15, 2021, 05:51:57 pm »

I just checked one of my latest tape dumps - and I see character 255 (FFh) immediately after a CR with no other characters after the last BASIC program statement.

Example:

Code: [Select]

190 END[CR]
[CR]
[FF]

Yes, 4924 service manual page A-3 description of end-of-file mark:

end-of-file mark: The byte (hexadecimal FF) written onto a tape to mark the logical end of a file.

Likely only written by Tektronix on SAVING ASCII PROGRAM files - I don't see it on ASCII DATA files, and the BINARY DATA type bytes encode EOF as type 7

WaveyDipole · « **Reply #191 on:** July 16, 2021, 08:23:06 am »

I knew I saw DC3 recently somewhere....

From the 4924 service manual, 2-09. No description is given for its purpose though.
[ Specified attachment is not available ]

mmcgraw74 · « **Reply #192 on:** July 16, 2021, 12:14:07 pm »

See page 7-42 in the 070-2056-01 4050 Graphics System Reference manual section of the FIND statement usage of [CR][DC3] to terminate the file header string:

mmcgraw74 · « **Reply #193 on:** July 16, 2021, 06:20:24 pm »

I tried to figure out why OLD command was not working, but I was not successful.

WaveyDipole · « **Reply #194 on:** July 17, 2021, 07:50:20 am »

I haven't worked it out either yet, but FIND followed by OLD works here via the terminal. I noted that your second image of the console output shows only the debug messages from the FIND command, but nothing at all from OLD, so it looks like OLD is not being received but I don't know why.

In the graphic we can see a UNL during the first ATN phase, but it is completely missed - DAV goes down on the next byte - hex 20. We also see SRQ asserted. Why and by which device? This might be causing the Tek to attempt a serial poll, but I am not seeing GPIB command 18. After the missed UNL things appear to go awry.

Is there a chance of getting another capture of the trace from FIND + OLD please? Could you also enable //#define DEBUG_DEVICE_ATN please. It might be best to do two separate scans first of the complete FIND which should show us the state of the GPIB bus when it is completed, and then the attempted OLD.

mmcgraw74 · « **Reply #195 on:** July 17, 2021, 05:09:21 pm »

mmcgraw74 · « **Reply #196 on:** July 17, 2021, 05:39:00 pm »

If I CD to a directory manually, FIND a data file with two numbers per line, INPUT A,B - the first two numbers are correct.
However, the second INPUT A,B command done manually, results in the numbers in incorrect order.

Here are the commands:

Code: [Select]

PRI @5,19:"ADVENTURE"
FIND @5:1
INPUT @5:A,B
A
 1
B
 133488
INPUT @5:A,B
A
 1641035
B
 5
INPUT @5:A,B
A
 92813
B
 8

Here is the first couple of lines of the contents of the /ADVENTURE/1 ASCII data file (each line is [CR] delimited:

Code: [Select]

   DATA 1,133488,1,6771679,2,36315,2,8849417,3,4673330,4
   DATA 1641035,5,1987117,6,234943,6,387847,7,7400652,8
   DATA 92813,8,249958,9,9462081,10,2517217,11,7523733,11
   DATA 7763223,12,1512460,13,8969927,14,7412167,14,12721

You had asked before whether the "DATA" in the file above would interfere with INPUT of the variables.

Here is page 10-22 of the BASIC Reference showing how Text is ignored in extracting a VALue from a string:

The Emulator should continue reading from the same line if the contents have not been consumed.
It appears the Emulator is reading the second line to satisfy the second INPUT command and the third line to satisfy the third INPUT command.

I think the FIND command is not terminating properly, because I wrote a program to run all the test commands above and the program generates an error on the line number with the FIND command and stops the program execution.

Likely the Tektronix must timeout on the GPIB bus condition if the FIND command is typed individually.

I may have been able to capture the FIND command typed manually:

Here are the waveform and trace listings:

BAD_FIND.zip (1.98 kB - downloaded 19 times.)

Sorry the columns are in a different order in my latest trace listings, I eliminated the SRQ signal - which appears to be mysteriously wiggling in the trace. I also eliminated the STATUS bits which included the SRQ pin. Maybe the emulator is not setting the SRQ to output mode - or is initializing it as zero?

mmcgraw74 · « **Reply #197 on:** July 17, 2021, 11:01:18 pm »

I uploaded a new microSD card zip file for testing, including my Adventure game with data files converted to INPUT format.

WaveyDipole · « **Reply #198 on:** July 18, 2021, 09:05:56 am »

Thanks for the update to the SD files.

In the meantime, I did spot something in the information your posted which may possibly have a bearing. It seems that the emulator responded to UNL but not to UNT. It was also responding to UNT and UNL only after the attention period had ended so I did wonder whether that might be causing a timing issue. You mention nthat enabling DEBUG_DEVICE_ATN cause OLD work (sort of). Since all that does is print more messages to the console, which, in effect, takes more time, that also might indicate a timing issue. I have posted an update that should ensure that state changes in response to UNL and UNT happen within the attention period. Whether it fixes the problem remains to be seen....

I haven't looked at the problem you reported with INPUT yet.

mmcgraw74 · « **Reply #199 on:** July 18, 2021, 12:07:43 pm »

Thanks, I'll check out your new version.

It also appears that each INPUT command may consume an entire ASCII line of characters, so in the Adventure files I uploaded, I changed the DATA files to match the program INPUT statements. I also removed spurious characters like quote marks for strings and "DATA" in the numeric ASCII DATA files. I did a test of an INPUT statement of a character string with quotes and the resulting string had the quote characters included - which is not what I wanted. Without the quotes, the strings are terminated by [CR], which is what is needed.

All of my prior ports of Adventure were actually using binary data files - created with WRITE statements and consumed by READ statements. Binary data files will not have [CR] termination as the data headers define exactly the type of variable and exactly the length.

I'm hoping your UNL/UNT changes will fix the INPUT (and other) command termination.


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