Atari 810 not loading disk

[spinnaker15136]

Just dragged my Atari 800 and 810 out of storage fro 30 years. The 800 powers up and I am getting video and sound out,

 

I connected the 810. It powers up and goes through its startup procedure. But is I power up the 800 with no cartridge the disk does not load. If I insert the BASIC XL cart and type DOS the Atari goes right to the memo pad.

 

 

I disconnected the SIO cable from the drive and tried looking for data and clock out with n\my scope but I see no transitions

 

 

Data Output: Low and remains low

Command: High and stays high

Clock Out:: : High and stay high.

 

 

I did a continuity test of the cable and it looks good.

 

The 810 is not connected. Is there something that needs to be jumpered that tells the computer there is a device on the serial port before it sends data?

 

Edit: I see that data out is open collector. I added a 10k pull up to 5V. Still no data out. . Just remains high. Trying to figure out how to send data out. I did it before,built my own Rs232 interface, but that was 30 years ago.

Edited April 21, 2019 by spinnaker15136

[+Nezgar]

When you say it 'goes through its startup procedure', do you mean the following:

1. Spin up, seek head to track 0

2. idle some seconds spinning

3. seek to track 39, spin down

 

If the drive is doing that, then it means at least the ROM, stepper, and basic mechanical functions are working.

 

Next, have you verified the drive select switches are set for Drive 1?

 

Lastly, do you notice any difference in the startup behaviour of the computer with and without the drive attached? If the computer interacts at all with the disk drive, you should here some different sounds/delays different to that with no drive attached at all. (Or not configured as Drive 1)

[spinnaker15136]

When you say it 'goes through its startup procedure', do you mean the following:

1. Spin up, seek head to track 0

2. idle some seconds spinning

3. seek to track 39, spin down

 

If the drive is doing that, then it means at least the ROM, stepper, and basic mechanical functions are working.

 

Next, have you verified the drive select switches are set for Drive 1?

810drivecode.png

 

Lastly, do you notice any difference in the startup behaviour of the computer with and without the drive attached? If the computer interacts at all with the disk drive, you should here some different sounds/delays different to that with no drive attached at all. (Or not configured as Drive 1)

 

Correct on startup.

 

Switches are set correctly.

 

No difference on startup sound or operation. Few seconds of buzzing then Memo Pad.

 

Might as well continue on this thread

 

http://atariage.com/forums/topic/290460-reading-writing-the-atari-400-800-serial-port/

 

since it has morphed into an 810 repair thread.