stuart@tellab1.tellabs.com (Rick Stuart) (06/17/91)
I have a memory card I'd like to get some help on! I have it sitting here in front of me fully populated but with NO documentation. It's an IBM AT memory card with five banks of memory. Each bank is made up of ten (2x9) 41256 120 nS memory DIP chips. I say that makes a total of 2.5 megs of memory! But because of the lack of documentation, I haven't got the slightest clue as to the type of memory (extended or expanded) this cards supports or what the two groups (1-6 and 1-8) of thumb switches do! My guess as to the above questions, well, other than the two PALs, there are about twenty eight TTL 7400 series chips on the board. I can't say for sure, but this doesn't look complex enough to support paged memory. As to the switches, I'd think one set would tell the board how much memory it has and the other where to put it!. But which is which, and how are the address values assigned to the thumb switches? Identifying marks... Well, there aren't many! First of all the silk screen says, surprise, MADE IN TAIWAN ROC. Next, more silk screening gives an FCC ID of "F1F48G PE505-16M". The next line is even more confusing. It says "ZERO MADE IN TAIWAN". What's a ZERO? Now for the best hint. On the back there is a sticker with the name "MAGITRONIC 615". I'd been told MAGITRONIC was a computer parts mail order house which also sold it own brand! Could this be one of their cards? Is 615 the model number? Is MAGITRONIC sill open? I can't find their phone number! Mail all hints to me! Some of these news groups have way to many postings. If the responses I get have an any type of general appeal, I'll summerize and post to the net. ...thanks, Rick Stuart