On Wed, Jan 24, 2018 at 9:45 AM, Fred Cisin via cctalk <cctalk@classiccmp.org> wrote: > > Does ImageDisk or Teledisk support it? > If so, then with the ED controller and one of these drives from Chuck, you > could image things such as the "4 Meg" floppies from NeXT. (4M is the > UNFORMATTED capacity of the 2.8M disk, and NeXT marketing thought that "4M" > sounded better than the "2.8M" formatted capacity) >
The ImageDisk 1.18 source code is available to inspect to answer the question. If there is something special that software needs to do to select a 1000K bps data rate I don't see anything in the ImageDisk code which does that. What does software need to do to select the 1000K bps data rate for 2.8M mode? http://www.classiccmp.org/dunfield/img/index.htm imd.c: unsigned Mtext[] = { // Translate Mode%3 to actual data rate 500, 300, 250 }; /* * Initialize data transfer mode (rate and density) * and update status display. */ void initmode(void) { unsigned x; Mfm = (Mode / 3) ? 0x40 : 0x00; out(FDC+5, x = Mode % 3); w_gotoxy(3, 0, swin); w_printf(swin, "%3uk %cD", Mtext[x], Mfm ? 'D' : 'S'); }