Tektronix 4051 RAMPACK - new design

[Bob Rosenbloom]

I was contacted by Micheal D. Cranford from the Tektronix Museum up in 
OR about
a design for a ROM module for the Tektronix 4051 graphic computer. It 
looks to be a very
useful item. See the description below. He's looking to build up some of 
them and make them
available. Cost would be about $100 each, assembled. He needs seven 
people to make it
worthwhile, I would take two, so we need five more people.

Anyone interested? Let me know!

Bob

_____________________________________________________________________________________

Bob:

I just saw your website today since another ex-Tek friend pointed it out 
to me.
I am currently nearing the completion of a RAMPACK for the 4051. I am making
this for the Tektronix Museum located in Oregon (http://www.vintagetek.org/)
which is totally maintained by former Tektronix employees.
The purpose of the RAMPACK is to effectively replace the mag tape drive 
since
the latter requires mag tape cartridges that are no longer made and the 
tension
bands degrade over time and fail. The lack of functional mag tape 
cartridges can
quite severely limit the usefulness of the 4051.  Since the Tek museum 
cannot
demo the 4051 very well due to the lack of reliable mag tape cartridges 
and any
user created programs disappear with powering down, I decided to create the
RAMPACK. I had actually started working on that decades ago when I was 
at Tek
but at the time it was just for speeding up file manipulations and that 
RAMPACK
was totally DRAM based.  The new version in contrast is non-volatile and 
it holds
far more data.

Note that this is a plug-in ROM PACK and it does not require altering 
the mag tape
drive or the 4051 computer in any way. The RAMPACK contains about 2MB of 
high
reliability guaranteed 100+ years of data retention time flash memory, 
which totals
to at least seven DC300A mag tape cartridges worth of data.  In actual 
practice it will
hold more than seven cartridges worth since the mag tape storage is 
inefficient with
small files. As an example a DC600 cannot hold 256 files of minimal 
length (768 bytes)
since each inter-file gap takes nearly 4 inches of tape. In contrast my 
RAMPACK can
hold 511 files of 4KB each.

You create and access RAMPACK files just like any other GBIP device on 
the 4051.
Each RAMPACK has a unique IO address and multiple RAMPACKs can be installed
at the same time. Simple examples include (the below assumes 
installation in the
right rear slot in the back of the 4051):

1.      FIND @51:1

2.      MARK @51:2,4096

        MARK 2 files that are 4KB byte long. Note that marked files will

        always be multiples of 4KB in size, and the MARK command will

        automatically pick the smallest multiple of 4KB that includes the

        user specified size.

3.      SAVE @51:

4.      FIND @51:1

5.      OLD @51:

6.      FIND @51:2

7.      PRINT @51:A, A$

8.      CLOSE

9.      FIND @51:2

10.     INPUT @51:A,A$

11.     Etc.

There are about 23 functions that support ASCII program and ASCII or 
BINARY data
files, write protecting arbitrary files, SAVE and OLD/APPEND for SECRET 
programs.
listing the details about all of the RAMPACK files (the equivalent of 
TLIST), checking
the current file status, naming each file (names can be up to 24 ASCII 
characters long)
and a whole bunch more.  The RAMPACK can also update its own firmware.

-- 
Vintage computers and electronics
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