Date   : Mon, 25 Jun 1990 18:53:16-EST
From   : John C Klensin <KLENSIN@INFOODS.MIT.EDU>
Subject: DEC Rainbow

Marek (md33+@andrew.cmu.edu) writes:

>Rainbow has a terminal mode, but it does not seem to be
>intelligent (i.e. up and downloading files from the host,
>using the programming features of the modem, etc.).
   In terminal mode, it is a VT102 with a funny keyboard.  Period.

> What I need is a good terminal program. I have no technical
>documentation necessary for writing one. Does anybody
>have a terminal program for Rainbow?
   There are good versions of kermit and all the usual other things 
available for this machine.  Most of them provide VT10x emulation, with 
some ability to use the bigger keyboard, and whatever file transfer things 
come with them.  These should be in the archives.

>Another question is: Does anybody have software for
>reading/writing PC 360K floppies on Rainbow? Rainbow
>has MS-DOS and 400K floppies - it must be technically
>possible.
   Not a chance.  That cute little diskette drive you are looking at--into 
which both diskettes go "write side out", has only one motor and one set of 
heads *per diskette*.  So, it is 400Kb single-sided, in its own unique 
format.  There is software around that will run on AT-class MessDOS 
machines that use 1.2Mb floppies that will write and read the Rainbow 80 
track single sided format (we've had pretty good success with MediaMaster 
(tm)).  And you should note that the Rainbow has special firmware that 
permits it to read *single-sided* standard PC diskettes (180K), which can 
be recorded on any PC.  It can sort of write them, too, subject to the 
restrictions about writing on a narrow-headed machine for a wide-headed 
machine (e.g., the diskette should be *very* blank before you start, but 
formatted on the wide-headed machine).  Reading doesn't take anything 
special, just format the disks single sided in the IBM environment, write 
on them, put the diskette into the Rainbow, and read or copy as usual.
  But there is no way to read or write an IBM 360K diskette on the 
Rainbow--not enough heads in the right places.  And no way to write or read 
Rainbow diskettes on an IBM 360K drive--not enough tracks.
  Various third-party vendors make, or used to make, IBM-compatible 360Kb
drives that could be attached to the Rainbow, but they are--or used to be--
sufficiently expensive that parking an IBM clone next to the Rainbow as a 
diskette device and running a serial wire between them was often a more 
cost-effective solution.
    --john klensin
    Klensin@MIT.EDU