Hello everyone.
I have a Mac 512K that just displays that checkered pattern at boot.
I already replaced the ROMs with those of a working Plus.
In fact, even without any ROM, the pattern is the same.
The continuity of all ROM pins is fine and voltages are ok, too (recaped analog board).
I was also poking with the oscilloscope and found that pin 8 of VIA (PA6 - vid.pg2) has no signal.
Can it be a problem with VIA or it shouldn't interfere with the boot?
I appreciate any help. Thanks.
I have a Mac 512K that just displays that checkered pattern at boot.
I already replaced the ROMs with those of a working Plus.
In fact, even without any ROM, the pattern is the same.
The continuity of all ROM pins is fine and voltages are ok, too (recaped analog board).
I was also poking with the oscilloscope and found that pin 8 of VIA (PA6 - vid.pg2) has no signal.
Can it be a problem with VIA or it shouldn't interfere with the boot?
I appreciate any help. Thanks.