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[KAYPRO 10] Boot Problems! Help?

OK, so some chips need reseating. Blinking floppy LEDs is the correct behavior for the monitor ROM. It is waiting for input on the serial port.

There may be other chips that need reseating. Perhaps that's a first thing to try.
 
Already tried to reseat all other ICs (except the ROM with the new burned EPROM, but I told you that I retried it also), and before I apply cooling spray on all ICs and capacitors to see if something changes, nothing happened.
Meanwhile I tried 2 different Null Modem / X-Over cables, connected to the Kaypro 10 Serial Connector (not Modem of course) and on the other end a IBM Thinkpad A31 with a real RS232 and Windows XP with Hyperterminal was connected.
I tried 300 baud N, 8, 1 with no handshake, with x-on/x-off and with hardware handshake, no success. Only directly after switching on the Kaypro, some obscure characters appear, but nothing later.
I can type in within Hyperterminal, what I like, no effect. Same with the Kaypro keyboard, except that every keystroke makes a very short piezo buzzer sound.
 
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I will give up. I tried also 9600 baud, with 8 Bit data, no parity, 1 stop bit, no flow control (because it's the most simple setting), nothing happens in Hyperterminal (no, not with an USB adapter, yes, with a real RS232).
I wish there would be a second diagnosis ROM with an initial startup message and some initial automatically started memory tests for the assumption/the case that the CRTC is working (yes, there could be also the case that the CRTC is dead, but this a requirement you will know in advance). I am not an expert in Z80 assembler (I am only familiar with x86 assembler code and computing languages like 'C'), so I guess disassembling the emergency monitor ROM is not an option for me, and so it's also not an option to modify it by myself.

Will try to hand over the sick Kaypro 10 to another Computer Collector, that will be the best choice.
 
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You saw the floppy drive LED blinking, so we know the ROM is running to the point that it is watching for input on the serial port. Most PCs require handshake before allowing a program to connect to the serial port, this includes the USB-serial dongles. The Kaypro should be asserting the necessary handshake, provided the cable hookup is complete.

The CRTC is one of the most complicated parts of the core hardware, from the perspective of points of failure. Depending on that for operation is counter-productive. I could work on a version of the ROM that used the CRT and keyboard for interaction, but that is a separate project. The code to manage the CRTC takes up a lot of space, we'll have to see if there is enough space left for the necessary diagnostics. Might not fit in 4K (2732) anymore, which limits its usefulness.
 
May be this disassembled ROM listing from an OMNI4 System (a modified Kaypro 2X I guess) can help to get an idea how the CRTC is initialized and used.
It's from 2015, unfortunately not anymore available (from hackaday.io).
 

Attachments

finding the CRT code for Kaypro is not the problem, there's even the original source code from the "universal ROM" available. That may no longer fit in a 2732, though. and the effort to combine it with the monitor code is not trivial. It is not something that I will get to this week.
 
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