Michael J. Mahon wrote:
David Wilson wrote:Michael J. Mahon wrote:A machined-pin socket and some wire can be made into an adapter to allow a 2716 to plug into the 2513 socket. The same kind of adapter is needed to replace any of the Monitor/BASIC ROMs.At least the Monitor/BASIC ROMs have all but 3 pins in common. A 2513 => 2716 adapter would have the following pinout: 2513 signal 2716/2316B 14 VA 8 15 VB 7 16 VC 6 17 DL0 5 18 DL1 4 19 DL2 3 20 DL3 2 21 DL4 1 22 DL5 23 4 O1 10 5 O2 11 6 O3 12 7 O4 13 8 O5 14 11 /E 18,20 24 Vcc 24,21 10 Gnd 12 1 Vgg n/c 12 Vdd n/cHmm--that's pretty bad! That would take *two* sockets and, preferably a small PC board. I'm surprised that two such different 16K ROMs were used on the same main board!
I see that I was spoiled by the later (//e) design! The 2513 is a 64x8x5 ROM that is *exactly* a character generator ROM! I'm no longer surprised. ;-) And adapting a byte-oriented ROM would require a small circuit board with, at least, an addressable latch, not just an "adapter"--sorry for my confusion. -michael New, faster SUDOKU v2.0 solver for Apple II's! Home page: http://members.aol.com/MJMahon/ "The wastebasket is our most important design tool--and it's seriously underused."