I meant to email you but haven't gotten around to it. It turns out that I thought I had a Model I with the same problem. It turns out that I do have video,...
Hi David, Sounds like fun, I've got 2 and I would like to get at least 1 working, It's actually kind of fun and a learning expierence. It's been a while since...
One of the Mod Is I fixed had bad sync and it ended up being a blown 74C04 part. I'm using a handheld scope I bought from American Science and surplus. It...
Hello, Does anyone know where I can get the pinout for the keyboard connector on the model 4 gate array system board? The 20 pin connector appears to be...
... I think the Model 4 technical reference has this information. If you can't find a copy, I have a copy of the Model 4 Service Manual (which includes the...
... OK, I went ahead and put a copy of the PDF for the Model 4 tech. ref. manual at the following URL. It includes information for the Gate Array. This isn't...
... Worked on one today, the screen is out of sync and is sort of twisted and I can't make anything out on it, although there appears to be some white where...
I finally got one to display something semi-intelligible on the screen. the MEMORY SIZE prompt comes up as LDLNRX RHZD and there is some random graphics on the...
Very nice! Compare the bits that make up the ASCII values in "MEMORY SIZE" vs. "LDLNRX RHZD" and see which bit is dropping out or stuck. That should give you...
... bit 0 is obviously allways seen as 0... push enter a few times then FORX=0TO255:POKE15360+X,X:NEXTX will display the whole table and will probaly start...
Good point David. It looks like bit 0 is bad since many characters are off by one. I would suspect bit 0 being bad somewhere in the video section. For example...
Oopps, I guess I meant to say that one of the input address lines could be bad on the character generator, not one of the output data lines. The characters do...
... To see if it is the character generator check the graphics, they don't come out of the character generator. for example push enter a few times then ...
Hey Guys, I swapped out a 2102 (Z48) with a pull from an extra board, I'm Now getting a solid Memory Size and Picture is in sync. It does seem like I'm getting...
Congrats! By replacing the cracked NAND chip, you fixed the video sync and it looks like your Model 1 is almost working. I had the same problem (in 1981) that...
G'day all, I am starting the preliminary design work of my fpga implementation of a model 1. I want it to have a hard disk, but I have never owned a real...
Most if not all of the emulators do emulate hard disks. You might want to play around with them a little bit to get an idea of how it all works. I have a set...
Hi, Just a note to let people know that I've shifted the System 80/Video Genie website to a new domain. I'm aware one or two of you may have links to it from...
... It's taking a lot longer than I originally planned, mostly because I have decided that if I'm going to all the trouble and expense of designing and making...
... I'd be very interested in your progress. Have you seen my project page? <http://pacedev.net/> <http://pacedev.net/forums/showthread.php?t=11> Regards, --...
Hi, There was a BASIC compiler for Level II BASIC published in 80 Micro. I believe it had several revisions published over the years. I was interested in...
Having problems with message search?
Fill out this form to ensure your group is one of the first to be migrated to the new message search system.
