Hello there !
Finally I got my scrap rescued Macintosh Plus alive !
The system start, make 'bong' and then display a floppy with a cross or a question mark if I put a blank floppy in the drive...
I download 6.0.8 800 k floppy images.
Then from a working SE/30 I made a boot floppy with the 'system tools' image using diskcopy.
I say "successfully" because the SE/30 can boot without error with this floppy.
Putting this floppy into the Plus and he smile and start to boot... then floppy read, head moves etc... I see the welcome message.
But at some point I get an "illegal instruction" or, less frequently, a "illegal address" error... Then I have to restart the computer.
I noticed that the Plus, sometime, even not start to boot and directly eject the floppy with a question mark or cross in the icon.
It is like if the Plus write something to the floppy during the boot because at that point I have to rewrite it into the SE/30 to use it again.
I also try to boot from scsi + bluescsi + a disk image make with minivmac (100 mo blank disk + 7.0.1 fresh install). The Plus dont boot from scsi. I just see the green light flashing rugularly on the bluescsi and the icon waiting for a suitable floppy.
I have two way to search : bad "reading" from the floppy drive or something wrong into the processor board (rec C).
Because the boot start well my opinion is for the second option...
I have a second logic board (rev D) which, at the same place, give nothing expect strange sound and fuzzy display at startup.
I already cross memory modules and rom as far as I can with what I have here but with always the same result.
I have no ground clip for this rev D board. Is that important ?
At this point any advice will be helpful. I have a 150 MHz scope etc.. so measure and testing is possible with some indications and help.
Thanks a lot.
Philippe
Finally I got my scrap rescued Macintosh Plus alive !
The system start, make 'bong' and then display a floppy with a cross or a question mark if I put a blank floppy in the drive...
I download 6.0.8 800 k floppy images.
Then from a working SE/30 I made a boot floppy with the 'system tools' image using diskcopy.
I say "successfully" because the SE/30 can boot without error with this floppy.
Putting this floppy into the Plus and he smile and start to boot... then floppy read, head moves etc... I see the welcome message.
But at some point I get an "illegal instruction" or, less frequently, a "illegal address" error... Then I have to restart the computer.
I noticed that the Plus, sometime, even not start to boot and directly eject the floppy with a question mark or cross in the icon.
It is like if the Plus write something to the floppy during the boot because at that point I have to rewrite it into the SE/30 to use it again.
I also try to boot from scsi + bluescsi + a disk image make with minivmac (100 mo blank disk + 7.0.1 fresh install). The Plus dont boot from scsi. I just see the green light flashing rugularly on the bluescsi and the icon waiting for a suitable floppy.
I have two way to search : bad "reading" from the floppy drive or something wrong into the processor board (rec C).
Because the boot start well my opinion is for the second option...
I have a second logic board (rev D) which, at the same place, give nothing expect strange sound and fuzzy display at startup.
I already cross memory modules and rom as far as I can with what I have here but with always the same result.
I have no ground clip for this rev D board. Is that important ?
At this point any advice will be helpful. I have a 150 MHz scope etc.. so measure and testing is possible with some indications and help.
Thanks a lot.
Philippe