Image Map Image Map
Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 22

Thread: Original Tandy 1000 no boot

  1. #11
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    I've tried the floppies that came with this machine in another machine.. one has mechanical issues.. the other is a bit strange.. I have it set as drive a.. but when I try to access drive a with it connected to one head of the double floppy cable, it spins without reading or lighting up. If I connect to the other header on the cable, it lights up but does not spin.

    I must be forgetting something about floppy drive jumpering?

  2. #12
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    Looks like I have bigger problems. I went to power up the 1000 after figuring out the jumper settings on one of the two drives. But now instead of getting a post, I get a blank screen and a continuous screeching noise from the speaker. Ugh

  3. #13
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    This is what it is doing now:

    https://youtu.be/yZtWFSJkP_s

  4. #14
    Join Date
    Mar 2016
    Location
    Georgia, USA
    Posts
    543

    Default

    Quote Originally Posted by falter View Post
    This is what it is doing now:

    https://youtu.be/yZtWFSJkP_s
    Spunds like unmuted Tandy sound chip random noise. I believe your bios is not being seen or is corrupt, muting that chip is one of the first things it does I believe.

  5. #15
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    I wonder if I could borrow the bios chip from my working 1000ex to test that?

  6. #16
    Join Date
    Mar 2016
    Location
    Georgia, USA
    Posts
    543

    Default

    Quote Originally Posted by falter View Post
    I wonder if I could borrow the bios chip from my working 1000ex to test that?
    I don't know. I doubt it would work.

  7. #17
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    Apparently it does. The 1000 ROM worked fine in the EX. But changing ROMs in the 1000 does not produce anything.

    A couple of times on power up I got some 'snow' on the 1000..

    If I had to lay a bet, I'd bet it was something to do with memory.

  8. #18
    Join Date
    May 2011
    Location
    Outer Mongolia
    Posts
    1,470

    Default

    Did the 1000 ROM recognize and use all 256k built in RAM in the EX? If so that's... interesting.

  9. #19
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    No... it only sees 128K.

  10. #20
    Join Date
    Jan 2011
    Location
    Vancouver, BC
    Posts
    4,578
    Blog Entries
    3

    Default

    Okay so I have done some checking around. Voltages from the PSU look good. I see clock signals being divided into correct frequencies ok. But there is no activity between the CPU and 128K ROM. I have light 'snow' on the screen, persistent tones from speaker.

    One thing that is odd.. probing the READY line on the CPU it it is high, however if I hit Reset a random number of times I will sometimes see an inconsistent signal there.

    Presently am trying to understand how the 8284 works and why occasional reset causes it to 'leak' signal onto the ready line, or if something should be there.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •