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[KAYPRO 10] Boot Problems! Help?

Great news! Yes, please do try the ROM out on the K2 as well - provided it makes sense (depends on the symptoms, the ROM probably won't help trace smoke back to it's origin ;-) And keep providing feedback. Efforts like these will help write the "Troubleshooting Kaypros" document, let alone improve the monitor. I made the change to the T FLPY (et al.) output, version 2.3 is now out there. Hopefully that will help in the future, too.
 
Yeah, there's a whole series of diskettes needed, although I think the first one will get you a bootable harddrive(?). Maybe 2 is also required... I forget what I figured out going through that. Do you have the rest of the images? They should be "out there" someplace.
 
Regarding the "T CRTC" problem, I am also seeing that on my 2X. I obviously have something broken in that code, and will have to work on it some more. Stay tuned... but don't throw away your SY6545's yet! (yet another subtle difference between simulator and real hardware).
 
ah old hardware... got to reinstall a reload, parked the head to shut it down.... and then the hard drive fails on boot now BDos error , I think the TM502 has just lost its last breath.
I wonder if I can just slap another hard drive in it. or do I need to make a special process... ?
 
I don't have experience with that, but I hear that some other drives may be compatible with the controller. Of course, they have to use the same interface plus need to have >= geometry. There's also a Kaypro FreHD solid-state replacement.
 
FYI, I found the problem with the T CRTC command. Turns out, the 6545 might trigger the Update bit multiple times during a single retrace, and I was assuming that happened only once. So, I needed to keep resetting the Update bit while waiting for it to go "off" (stay off). It now works on my 2X, ran the command many times (90+), and with a larger update count (6), and saw no hangs. Version 2.4 is out there.
 
I have started work on a Diagnosing Kaypros Guide here: http://sebhc.durgadas.com/kaypro/diags.pdf. The scope of the document is after you've verified power supplies, capacitors, etc and are able to run the monitor.

The latter half of the document is just copy-over from the monitor document - still to be written. But it's a start. Let me know what you think, additions, corrections, etc.
 
@durgadas311 - May be you have an idea where/how to start with a non-working Kaypro 10... you can switch the computer on, but only a small cursor appears on the screen, nothing else.
There is no ROM message, no disk drive action (drive select or similar), no hard disk action (no LED blinks).
The power supply delivers all voltages as expected. Someone checked all TTL and other chips with a cooling spray before I got it.
The connectors were all disconnected and reconnected.
The first step would be getting a ROM message I guess - but what should I check first in the described situation ?
 
Depends on the ROM you have, but for the 81-302 ROMs the CRT controller is initialized (cursor appears) and then the HDD controller (WD-1002) is reset. It is possible that the reset operation hangs, due to a faulty HDD controller. between CRTC init and message displayed it resets the WD-1002 and then initializes high memory. I don't think the high memory init can hang.
 
I take that back, I don't think the reset WD-1002 can hang. So, perhaps it is trying to "print" the message to the screen but the CRT circuitry is not functioning correctly and it is hung waiting for the ready signal to write data to CRT RAM. If you are going to replace the CRTC, be certain to get the correct version. The 6545 or the 6845E ("E" is vital).
 
Thank you for your fast answer. I would prefer to be sure that the CRTC is defect. Are there any kind of test procedures or measurements for that ? I mean, I do not have a 2nd Kaypro 10 to compare voltages and oscilloscope curves, so this would be very helpful to get more than only the schematics. I own a Kaypro IV, too, but there exist no CRTC in the IV for a quick exchange test.
For example, how can I be sure that the Z80 is working ? Are there any easy test procedures to recognize this ?
 
There is some evidence that the CPU is at least partially functional, since the CRT chip is getting initialized. If the CPU could not run at all, the CRT chip would never get initialized and there wouldn't be any video at all. Any further testing of the CPU probably has to be by running software.
If you can burn EEPROMs/EPROMs, and can hook up the serial port to a PC, you can try and run the monitor ROM I provided links to earlier. Documentation is in http://sebhc.durgadas.com/kaypro/monitor.pdf and http://sebhc.durgadas.com/kaypro/diags.pdf. There are procedures documented there on how to check out basic operation of the CRT chip. I also have a standalone ROM image for a memory test, which is a good thing to try if even the monitor ROM won't run correctly.
 
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