General Category > Lisa Troubleshooting and Repair
New Lisa Build does not work - please help
aihk:
--- Quote from: greniu on January 21, 2025, 04:01:21 pm ---Dear all,
I am restoring my old Apple Lisa 2/5 I/O board. I have a problem that I cannot get a correct boot image after turning on the Lisa but instead the screen displays garbage. During the turn on Lisa one beep appears (sometimes two short beeps). The board worked correctly before. I have a second good I/O board and after inserting it into the same Lisa there are no problems. So the issue is definitely somewhere in I/O board. Maybe someone knows this problem and knows hints where I should start with measurements on the oscilloscope?
Screen from boot process below. Thanks
--- End quote ---
My situation is the same as yours, did you solve this problem?
sigma7:
--- Quote from: aihk on March 28, 2025, 12:34:39 pm ---My situation is the same as yours, did you solve this problem?
--- End quote ---
Since this symptom can be caused by quite a few problems, the repairs necessary for two boards with this same problem may be completely different (or maybe the same).
I suspect the initial repair effort stalled at the steep troubleshooting hurdle... if you have access to some sort of test equipment (or willing to buy some), and some time, we can try to help diagnose to the component level.
edit: From the following discussion, it is revealed the situation is somewhat different, so the topic was split.
aihk:
--- Quote from: sigma7 on March 28, 2025, 05:51:44 pm ---
--- Quote from: aihk on March 28, 2025, 12:34:39 pm ---My situation is the same as yours, did you solve this problem?
--- End quote ---
Since this symptom can be caused by quite a few problems, the repairs necessary for two boards with this same problem may be completely different (or maybe the same).
I suspect the initial repair effort stalled at the steep troubleshooting hurdle... if you have access to some sort of test equipment (or willing to buy some), and some time, we can try to help diagnose to the component level.
--- End quote ---
I built the LISA myself, I suspect it's the memory, I have an oscilloscope and a multimeter. Now I don't know how to check for errors
aihk:
--- Quote from: sigma7 on March 28, 2025, 05:51:44 pm ---
--- Quote from: aihk on March 28, 2025, 12:34:39 pm ---My situation is the same as yours, did you solve this problem?
--- End quote ---
Since this symptom can be caused by quite a few problems, the repairs necessary for two boards with this same problem may be completely different (or maybe the same).
I suspect the initial repair effort stalled at the steep troubleshooting hurdle... if you have access to some sort of test equipment (or willing to buy some), and some time, we can try to help diagnose to the component level.
--- End quote ---
I uploaded the error sound, I'm new and I'm not sure what kind of error alarm sound it is
sigma7:
--- Quote from: aihk on March 29, 2025, 02:46:01 am ---I uploaded the error sound
--- End quote ---
Those are the "two lo beeps" indicating "no memory" per https://lisafaq.sunder.net/lisafaq-hw-rom_beeps.html
--- Quote ---
I built the LISA myself
--- End quote ---
Congrats, that's a big project!
Have you been able to test your boards separately in a working Lisa, or try a set of known-working boards in yours? Isolating the problem to a particular board will make troubleshooting a lot more manageable.
Navigation
[0] Message Index
[#] Next page
Go to full version