Possible PUTR bug?

[Fred Cisin]

I wish that I were to have met you 40 years ago!
Learning that stuff by error, error, error, trial, and error was 
inefficient.

--
Grumpy Ol' Fred     		cisin at xenosoft.com

On Sat, 11 May 2019, allison via cctech wrote:
> My Solution is easier, least for me.
>
> I have a few Z80 CP/M machines with 765A in it and if it can't read it
> its likely due to being hard sectored or M2FM.  I has 3.6, 5.25 and 8"
> and  the 5.25 are Teac FD55gfh which are dual speed and can do all
> modes. With my own software and utilities it does whatever even RX180,
> RX50, RX33, and RX22/23 formats from the DEC pool.
>
> The PC machine for when that stuff is needed is a DELL pizza box that
> has 32mb of ram and 486dx/66 (ISA/ISA16) and can run dos though NT4 as
> needed as I have a buttload of ST3660As as media for them (have two as a
> spare).  That machine uses a combo IO controller for the FDC seems to do
> what I ask of it.  Also an old Compag with similar features and PII and
> 32MB and also does Ethernet but the disk controller is a newer ISA16
> using a combo chip and most of the combo chips after late 90s-ish seem
> to have an even shorter VFO sync window (flash blindess).
>
> I neither expect nor desire modern machine with anything past NT4 to
> behave well with old disks.  Though Mini-ITX boards all seem to support
> everything and anything and have all the legacy ports.  They all run
> linux and if needed a partition (60mb of disk is trivial) for MSdos
> 6.22 or freedos.
>
> Oh, unless its under threat the OS is linux, freedos, or if required XP
> Though the latter is usually under VMware or Virtualbox on Linux..  I
> just got tired of all the winders hassles and requirements for insane
> hardware needs every few years.  Most stuff runs fine under dosemu or wine.
>
> As to RT11, I have run mostly V5.0x and as needed if a device required
> it a later driver borrowed from V5.04 or later.  It just seems to work
> with out much pain.
>
> As to running a RX50 on a PC...  That drive was a neat thing but its
> mostly the interface is incompatible with most standard floppies and
> a FD55A/B or any of the 48tpi 40 track drives will read and write the
> media.  I make a point of only using it on PDP-11 as transfer media,
> its low density so its marginal for much.  Keep in mine that drive
> select is used to select the A or B drive of a RX50 there is no side.
> They had a terrible track record for reliability.  I can put Two RX33
> [teac fd55gfh] in the same space and store more.  Some to think of it
> most Late PC 5.25 and 3.5 inch drives are incompatable with old standard
> [TM100 and that era] as many do not have a 1 of 4 drive select jumper
> and use the funky PC only twist cable.
>
> I neatly sidestep all of the cruft and hacks needed for super wizbang
> winXP and later machines.  I figure if I'm going to play with old
> hardware I need to retain the old hardware to maintain them.  So I
> retained the best of the best old PCs as they bulk of them are crap.
> I buy new hardware that is not neutered.  Mini/Micro-ITX board with
> atom or celeron CPUs (really all that's needed) are cheap and easily
> built up into linux boxes or if you must any of the older 32 bit
> winders incantations.
>
>
> Allison