Jerome Fine replies: I doubt that the M90 is any faster than the DEC PDP-11/93 since both use the same J11 chip. Not the M1 is definitely faster, although I would not necessarily believe the estimate that Mentec provides - DEC also used to exaggerate the speed of a new board. Also, does anyone know the cost of the M1? On the other hand, I am able to run at about TEN times the speed of an 11/93 when I use just a Pentium III 750 under Windows 98 and Ersatz-11. The hobby version of Ersatz-11 is free and even the commercial version of Ersatz-11 is probably less (at $ US 2999) than an M1 CPU. Not that there is anything wrong with an M1 if a real PDP-11 Qbus system is required. But it is possible to use a PCI <=> Qbus adapter when Ersatz-11 does not support the emulation of specific PDP-11 modules that are required. In that case, the increased speed of Ersatz-11 (up to TWENTY times the speed of an 11/93 with a Pentium IV 2 GHz (sigh and yeck at the same time) shows that software emulation has great advantages over a hardware solution for some applications. Sincerely yours, Jerome Fine -- If you attempted to send a reply and the original e-mail address has been discontinued due a high volume of junk e-mail, then the semi-permanent e-mail address can be obtained by replacing the four characters preceding the 'at' with the four digits of the current year.

Sridhar the POWERful wrote: My computer ( 600 Mhz ?? ) states not to use the seriel port faster than 9600 because the internal modem uses the irq line. sigh! -- Ben Franchuk - Dawn * 12/24 bit cpu * www.jetnet.ab.ca/users/bfranchuk/index.html

Well, I have used WinNT4.0Workstation and Visual Basic 6 to obtain realtime data from a board interfaced to a quadrature signal as a means of measuring the height of gas turbine engine blades. It worked quite well, and I was easily able to make 500 such measurements per second. The board simply supplied the current value from the quadrature signal, and in no way supplied a time base for capturing the value. The time base came William R. Buckley

I'm not sure what the current value of a 11/93 board is, but offering you a TQK50 and a RQDX3 for one is insulting! It's definitly worth a lot more than either of those or a KA650! Zane

Jerome Fine replies: I suspect that if you did make such a trade and then offered to make a trade based on 2 * (TQK50 + RQDX3) for one KDJ11-EB, the offer would be refused. That KDJ11-EB is still worth a fair bit. So while I did not use the "insulting" word, I don't think you have been offered a reasonable trade - in fact when I think about "insulting" as a description, I suggest that "stealing" might be a better description. But, then it is still just an 11/93 and unless you MUST have real PDP-11 hardware, it still runs at the speed of an 11/93 as compared to Ersatz-11 on a Pentium IV 2 GHz which will be about 20 times as fast. For development work, Ersatz-11 is usually OK, but I know of an application where even a PCI <=> Unibus Adapter used with Ersatz-11 does not work correctly. Sincerely yours, Jerome Fine -- If you attempted to send a reply and the original e-mail address has been discontinued due a high volume of junk e-mail, then the semi-permanent e-mail address can be obtained by replacing the four characters preceding the 'at' with the four digits of the current year.