On Sat, May 18, 2013 at 6:39 PM, allison <ajp166 at verizon.net> wrote:
  On 05/18/2013 04:50 PM, Dave McGuire wrote:
     Yebbut...having a grand old system like a
PDP-11 on "life support" by
 connecting it to a PC is something that I (and others) find extremely
 distasteful.  A standalone device would definitely have a market. 
 I agree.  Besides a whole pc is wasted.  All that is needed is a Beagleboard
 or RaspberryPi running linux and the TU58 emulation for two drives. 
Indeed.  For $35, the Raspberry Pi gives you a 3.3V serial port (just
add one chip to do level shifting), plenty of local file store for
disk or tape images, and enough I/O lines to implement an
LCD/push-button interface.
  Heck an 8051 can do that (see spare time gizmos
tu58em)! 
Yep, but building a solution around a Raspberry Pi is a lot cheaper
than rolling your own board.
  A more modern version could easily put a 8gb micro SD
effectively at the end
 of a serial port... a serial board is the easiest thing to build for PDP8... 
My memory was that back in the day when the TU58 was new, the PDP-8
community was very excited about inexpensive block-addressable storage
but it came to naught because the TU58 RSP protocol relied on "break"
to synchronize the host and the drive and it's not easy to send a
break from a pre-DECmate serial port.  I remember a lot of discussion
published in LUG newsletters, but I don't think anything was every
produced in the way of an OS/8 driver.
Serial ports and PDP-8s and Kermit certainly go well together.
-ethan