Hi,
I am wondering if anyone is able to help me at all?
I recently acquired an old Apple II EuroPlus system, has the disc controller card and 2 disc drives, no other expansion card of any type fitted.
When I turn it on, there is no beep and the screen displays a random load of characters and that's it, no further.
Any ideas as to what the problem may be?
I took a photo of the screen so you could see:
I read somewhere but I can't seem to find where I read it now, that it could be something to do with the RAM chips, most of the ram chips inside are D416C-2 or ones which say 4116 on them which I can't find any info on.
Maybe it is the ram or maybe it is something else.
I am hoping someone here has seen this before and has the solution, I am so eager to get it up and running and have a play. It is my first vintage Mac to my collection and would really like to see it working before I give up collecting vintage Macs before I have even started.
Many thanks for any help in advance.
4116 are 16k ram chips the 3 voltage type. If you want to google mk4116, you should be able to find a data sheet on them.
If they display is not changing, then DRAM (at least the part used for video display) is good and your problem is going to be either the Processor itself or interface between the processor and PROM or DRAM
I have kind of sorted it, I swapped over row C with Row E of the ram chips and the system now boots.
I can now load my AppleDos disk and use the computer.
Cant load some of the stuff from the disc though as some stuff on there required the language card but I am fine with that right now, just happy I got it working.
Just gotta swap the ram chips back 1 by 1 to figure out which one or two is faulty then I can replace.
Looks like the problem seemed to just be the ram, hopefully that is the only problem as the ram chips are pretty easy to find now I understand what chips they are.
*EDIT* whoops, for some reason my post duplicated itself.
just sent pm.
good idea to download the "apple II circuit description" as .pdf-file from apple documentation website within the so called "apple web ring".... probably asimoiv website.... it´s the "bible on troubleshooting the apple II" and contains detailed description of the apple II circuitary and a good troubleshoot list on commen errors and hardwarefaults of the spple II.